Daily cherry pick #35325

Remove all CMake options, modules, and deployment logic related to the
Qt GUI: BUILD_GUI, WITH_QRENCODE, WITH_DBUS, BUILD_GUI_TESTS, Qt 6.2
package discovery, FindQt.cmake, FindQRencode.cmake, the macOS app
bundle deploy target, and share/qt translation/plist files. Update the
Windows NSIS installer and ENABLE_IPC description accordingly.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Remove src/qt/test/ entirely and clean up references to test_bitcoin-qt
in src/test/README.md and doc/files.md.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Delete the entire src/qt/ directory, both GUI init implementations
(bitcoin-qt.cpp, bitcoin-gui.cpp), the Qt translation lint script, and
the Qt translation process doc. Update all references to bitcoin-qt and
bitcoin-gui throughout source files, CI scripts, contrib tools, and
documentation.

Remove -DBUILD_GUI=OFF and Qt package dependencies from CI scripts,
drop -DBUILD_GUI_TESTS=OFF from guix and libmultiprocess build scripts,
delete the Transifex config, and remove translation workflow references
from README, CONTRIBUTING, and release docs.

Remove the GUI

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

* nuke: assumeutxo (commit 1 of 3) - drop user-facing surface

Delete loadtxoutset and getchainstates RPCs, empty all chains' m_assumeutxo_data,
drop feature_assumeutxo.py, tool_bitcoin_chainstate.py and utxo_snapshot fuzz target,
delete the now-orphan snapshot-related unit tests.

The snapshot machinery (ActivateSnapshot, PopulateAndValidateSnapshot, etc.) is
still in place but unreachable from outside the binary. Removed in the next commit.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

* nuke: assumeutxo (commit 2 of 3) - rip snapshot machinery

Delete AssumeutxoHash/AssumeutxoData/AssumeutxoForHeight/ForBlockhash and
GetAvailableSnapshotHeights from chainparams. Delete ChainstateRole, the
Assumeutxo enum, SnapshotMetadata, SnapshotCompletionResult, and the
m_from_snapshot_blockhash / m_target_blockhash / m_target_utxohash /
m_cached_snapshot_base / m_cached_target_block members on Chainstate.

Drop ActivateSnapshot, PopulateAndValidateSnapshot, MaybeValidateSnapshot,
DetectSnapshotChainstate, ActivateExistingSnapshot, HistoricalChainstate,
ValidatedChainstate, RemoveChainstate, LoadAssumeutxoChainstate,
ValidatedSnapshotCleanup, GetBackgroundVerificationProgress and the
snapshot-aware paths in CheckBlockIndex / LoadBlockIndex / LoadChainTip /
UpdateTipLog / MaybeRebalanceCaches.

Delete BLOCK_ASSUMED_VALID, BlockManager::m_snapshot_height, the
per-snapshot blockfile cursor array, and the NODE_NETWORK-flip on
snapshot load.

Drop the ChainstateRole parameter from BlockConnected and
ChainStateFlushed across validationinterface, node/interfaces,
zmqnotificationinterface, bitcoinkernel. Drop Chain::hasAssumedValidChain.

ChainstateManager still holds std::vector<std::unique_ptr<Chainstate>>
m_chainstates with exactly one entry; commit 3 collapses that to a
single unique_ptr.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

* nuke: assumeutxo (commit 3 of 3) - collapse m_chainstates to single chainstate

ChainstateManager::m_chainstates was a std::vector<std::unique_ptr<Chainstate>>
that could hold up to two chainstates (one snapshot-based, one background).
With the snapshot machinery gone, replace it with a single
std::unique_ptr<Chainstate> m_chainstate.

Rewrite every `for (auto& cs : m_chainstates)` loop to operate on the sole
chainstate directly. InitializeChainstate / ActiveChainstate / ActivateBestChains /
ResetChainstates simplified accordingly, plus the matching call sites in
init.cpp, node/chainstate.cpp, kernel/bitcoinkernel.cpp,
test/util/validation.cpp, and the consistency checks in CheckBlockIndex.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Remove the REST interface

Adds a binary that fetches Bitcoin Core's master branch, finds the
common ancestor with the current branch, then attempts to cherry-pick
each merged PR (merge commits) in order. Conflicts are logged and
skipped; the tool continues to the end and prints a summary.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

2424e5283672e10bc45cdbca1a8851308716b50c lint: doc: detail lint tool install methods (will)
5fefa5a654e2a1146c8abc9673e72d7bcbf2f757 Don't pin Python patch version (Sjors Provoost)
fd15b55c2ef607525d45f26ab3e7f3fc600e29af lint: use requirements.txt (will)
5f4d3383daa064d188ef8c6b1d9adbad3a67bcb6 lint: switch to ruff for formatting and linting (will)
a53b81ce4e649dd637a217686745a6f6c6c81ca5 lint: switch to uv for python management in linter (will)

Pull request description:

  Modernise our lint tooling by:

  \- Replacing pyenv + pip with [uv](https://docs.astral.sh/uv/) for better Python environment and dependency management
  \- Move uv ruff and ty to install via `COPY --from` multi-stage Docker image imports
  \- Moving ruff lint rules from hardcoded Rust array (in lint_py.rs) into a top-level ruff.toml
  \- Extracting all remaining pip dependencies into dedicated ci/lint/requirements.txt

  Extra rationale:

  `COPY --from` pulls pre-built binaries from upstream images instead of compiling/downloading at runtime. Containerfile layer optimisations reduce rebuild frequency further.

  Pinning tool versions in the dockerfile makes it more excplicit and easier to find.

  The tradeoff we make here is that there is no longer a single install script to install tooling on a local machine. However I think this is OK, as it currently only works for `apt`-based OSes anyway, and I don't think running the linter outside of the container is such a valuable use-case as it is with some of the other CI jobs.

ACKs for top commit:
  maflcko:
    review ACK 2424e5283672e10bc45cdbca1a8851308716b50c 🗿
  sedited:
    ACK 2424e5283672e10bc45cdbca1a8851308716b50c

Tree-SHA512: 32ef989c1e241cebe5f13da10abd23f6f63306591fd1f81880d688b886082bca17987591dc592c41fbb72278eba57b3cc6e786de7cfa80eb490ab34465d0119b
(cherry picked from commit 09a9bb3536718d0dffa6f797ddff907df6ef94f9)

fa9c919678c0d4926ff735eecf12562d99a7e691 refactor: Use ignore-list over verbose select-list (MarcoFalke)
fa9b01adecce7d2e2f0091a363bcf98cf5d5c378 ci: Enable ruff ambiguous-unicode-character checks (MarcoFalke)

Pull request description:

  Ambiguous unicode chars are unused and confusing. Worst, they can lead to bugs.

  So enable the ruff checks to catch them. Can be tested via:

  ```
  echo 'ZGlmZiAtLWdpdCBhL3Rlc3QvZnVuY3Rpb25hbC93YWxsZXRfZGlzYWJsZS5weSBiL3Rlc3QvZnVu
  Y3Rpb25hbC93YWxsZXRfZGlzYWJsZS5weQppbmRleCBkYmNjY2Q0Li4wYjhjNDQ2IDEwMDc1NQot
  LS0gYS90ZXN0L2Z1bmN0aW9uYWwvd2FsbGV0X2Rpc2FibGUucHkKKysrIGIvdGVzdC9mdW5jdGlv
  bmFsL3dhbGxldF9kaXNhYmxlLnB5CkBAIC0yMSwzICsyMSw4IEBAIGNsYXNzIERpc2FibGVXYWxs
  ZXRUZXN0IChCaXRjb2luVGVzdEZyYW1ld29yayk6CiAgICAgZGVmIHJ1bl90ZXN0IChzZWxmKToK
  KyAgICAgICAgIiIiQSBsb3ZlbHkgZG9jc3RyaW5nICh3aXRoIGEgYFUrRkYwOWAgcGFyZW50aGVz
  aXPvvIkuIiIiCiAgICAgICAgICMgTWFrZSBzdXJlIHdhbGxldCBpcyByZWFsbHkgZGlzYWJsZWQK
  KyAgICAgICAgIyBu0L5xYSAgIzwtIGlzIEN5cmlsbGljIChgVSswNDNFYCkKKyAgICAgICAgcHJp
  bnQoIs6XZWxsbywgd29ybGQhIikgICMgPC0gaXMgdGhlIEdyZWVrIGV0YSAoYFUrMDM5N2ApLgor
  ICAgICAgICBleGFtcGxlID0gInjigI8iICogMTAwICAjICAgICLigI94IiBpcyBhc3NpZ25lZAor
  ICAgICAgICBleGFtcGxlPU5vbmUjbm9xYQogICAgICAgICBhc3NlcnRfcmFpc2VzX3JwY19lcnJv
  cigtMzI2MDEsICdNZXRob2Qgbm90IGZvdW5kJywgc2VsZi5ub2Rlc1swXS5nZXR3YWxsZXRpbmZv
  KQo=' | base64 --decode | git apply

  git diff

  ruff check ./test/functional/*.py
  ```

  It should print 4 error types.

ACKs for top commit:
  stickies-v:
    ACK fa9c919678c0d4926ff735eecf12562d99a7e691
  willcl-ark:
    ACK fa9c919678c0d4926ff735eecf12562d99a7e691

Tree-SHA512: de226ec2feaf65a0a8b15606708cc390296be4492f41221f8a49f034b16e8fb62125342c6993f9d5c76bd4ae2db7343851b252a1b9140e27d6777f19a0b1605e
(cherry picked from commit 82733e61deea24cfd344aed36020675a15cc672e)

Daily cherry pick

Track which upstream merge commits were previously cherry-picked by
scanning our branch's commit messages for the "(cherry picked from
commit <hash>)" trailers written by -x. Switch the upstream log format
from --oneline to --format=%H %s so full hashes are used throughout,
ensuring reliable comparison against the stored trailers.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

contrib: cherry-pick-upstream: skip already-applied commits

Removes test/functional entirely, along with all CI invocations,
documentation, build-system hooks, and contrib scripts that depended on
it (contrib/testgen, contrib/message-capture).

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

The cycle node/utxo_snapshot -> validation -> node/utxo_snapshot no
longer exists and can be removed from EXPECTED_CIRCULAR_DEPENDENCIES.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Remove functional tests

Remove unused fuzz targets

Decrease the HTTP server threads to one

ca93ab808c488324990eb91ed8297a37dd10d580 doc: mention -DWITH_ZMQ=ON in BSD build guides (junbyjun1238)

Pull request description:

  The BSD build guides currently state:

  > If the package is installed, support will be compiled in.

  Since `WITH_ZMQ` defaults to `OFF`, this is inaccurate: installing the dependency alone does not enable ZMQ support. Update the wording to mention the required `-DWITH_ZMQ=ON` CMake option, matching `doc/zmq.md`.

  Docs-only change; no tests run.

ACKs for top commit:
  maflcko:
    lgtm ACK ca93ab808c488324990eb91ed8297a37dd10d580
  sedited:
    ACK ca93ab808c488324990eb91ed8297a37dd10d580

Tree-SHA512: d07b1b9748d8b6aa555c992608f8659b7e93d6587bbbb2170352342003e90a81592ddfa2abf3a26b8ebf1341142d8628cfc3faba0c4759655a91446afa5fc22a
(cherry picked from commit 5309c90542276f5357a75f0335cad949ae515d42)

0065f354a7e9435fbc64f2bdc7b2b695df90cf4c doc: clarify libfuzzer-nosan preset uses build_fuzz_nosan dir (ImMike)

Pull request description:

  Adds a clarifying note next to the first mention of the `libfuzzer-nosan` preset in the Quickstart, pointing out that it uses a different build directory (`build_fuzz_nosan`, per [`CMakePresets.json` L54](https://github.com/bitcoin/bitcoin/blob/master/CMakePresets.json#L54)).

  A reader following the quickstart with `--preset=libfuzzer-nosan` and then running `cmake --build build_fuzz` as shown would otherwise operate against the wrong (or empty) directory.

  Pure docs; no code changes.

ACKs for top commit:
  l0rinc:
    ACK 0065f354a7e9435fbc64f2bdc7b2b695df90cf4c
  maflcko:
    lgtm ACK 0065f354a7e9435fbc64f2bdc7b2b695df90cf4c
  sedited:
    ACK 0065f354a7e9435fbc64f2bdc7b2b695df90cf4c

Tree-SHA512: d73901112d259cec58746dff50fe3f9409e5b9826f0759f45478fe039bca851eb163036c60bdb215bfc66be79428b790742bbe8bc32b1ceaa2d6f80c17faf6d0
(cherry picked from commit 04003e1fa3754b7557255d82c9b6d7ce309b11c8)

032223f403d320c3c47c7d5932e333f306efcdc3 dbwrapper: reuse iterator scratch stream (Lőrinc)
7403c0f907df694af8c9ee7d43dc65041242ca21 dbwrapper: guard `CDBBatch` scratch streams (Lőrinc)
cb1ab0a716802dae31c395691c4b2f3e4e5d4cb7 test: cover repeated dbwrapper stream use (Lőrinc)
31ce729b28ec7b1013054518559c55c642ac778e streams: add `ScopedDataStreamUsage` (Lőrinc)

Pull request description:

  ### Problem
  `CDBIterator::GetValue()` cannot use `SpanReader` the same way as `::GetKey()` because values are deobfuscated in place before deserialization, so it still needs an owning mutable buffer.
  However, the current path allocates a fresh `DataStream` for every value read.

  The same local-stream pattern also exists in `CDBIterator::Seek()`, while `CDBBatch` already owns reusable key/value buffers but still manually reserves and clears them on every `Write()` and `Erase()` call.

  ### Fix
  Add `ScopedDataStreamUsage`, a small RAII helper for caller-owned scratch streams.
  It asserts that the stream is empty on entry (making accidental re-entry or concurrent use of the same scratch stream fail fast), and clears it on scope exit.

  Use it to guard the reusable scratch streams in `CDBBatch::Write()`, `::Erase()` and `CDBIterator::Seek()`, `::GetValue()`.
  The const read-side `CDBWrapper` helpers stay unchanged, since they can be called concurrently on the same wrapper and should keep using local streams.

  The production changes are preceded by tests covering repeated reuse on the same owning objects, including a failed iterator value decode followed by a successful read from the same iterator entry.

  ### Context
  Follow-up to #35128, #34483 and #35025.

  ### Reproducer
  `gettxoutsetinfo` gets an additional ~6% speedup on top of the previous iterator-key optimization:

  <details><summary>2026-04-24 | gettxoutsetinfo | i9-ssd | x86_64 | Intel(R) Core(TM) i9-9900K CPU @ 3.60GHz | 16 cores | 62Gi RAM | xfs | SSD</summary>

  ```bash
  COMMITS="2d5ab09f0dca4bfec0b365f5f431def2c0c9d70f 9e5fd595ae8ebeec74678c31a547fbc14f87bf89"; \
  BASE_DIR="/mnt/my_storage"; DATA_DIR="$BASE_DIR/BitcoinData"; LOG_DIR="$BASE_DIR/logs"; \
  mkdir -p "$LOG_DIR" && \
  (echo ""; for c in $COMMITS; do git cat-file -e "$c^{commit}" 2>/dev/null || git fetch -q origin "$c" || exit 1; git log -1 --pretty='%h %s' "$c" || exit 1; done) && \
  (echo "" && echo "$(date -I) | gettxoutsetinfo | $(hostname) | $(uname -m) | $(lscpu | grep 'Model name' | head -1 | cut -d: -f2 | xargs) | $(nproc) cores | $(free -h | awk '/^Mem:/{print $2}') RAM | $(df -T $BASE_DIR | awk 'NR==2{print $2}') | $(lsblk -no ROTA $(df --output=source $BASE_DIR | tail -1) | grep -q 1 && echo HDD || echo SSD)"; echo "") && \
  hyperfine \
    --sort command \
    --runs 3 \
    --export-json "$BASE_DIR/gettxoutsetinfo-$(sed -E 's/([a-f0-9]{8})[a-f0-9]* ?/\1-/g;s/-$//'<<<"$COMMITS")-$(date +%s).json" \
    --parameter-list COMMIT ${COMMITS// /,} \
    --prepare "killall -9 bitcoind 2>/dev/null || true; rm -f $DATA_DIR/debug.log; git clean -fxd && git reset --hard {COMMIT} && \
      cmake -B build -G Ninja -DCMAKE_BUILD_TYPE=Release && ninja -C build bitcoind bitcoin-cli -j$(nproc) && \
      ./build/bin/bitcoind -datadir=$DATA_DIR -connect=0 -listen=0 -dnsseed=0 -coinstatsindex=0 -txindex=0 -blockfilterindex=0 -daemon -printtoconsole=0; \
      ./build/bin/bitcoin-cli -datadir=$DATA_DIR -rpcwait getblockcount >/dev/null" \
    --conclude "./build/bin/bitcoin-cli -datadir=$DATA_DIR stop 2>/dev/null || true; killall bitcoind 2>/dev/null || true; sleep 10; \
      grep -q 'Done loading' $DATA_DIR/debug.log && grep 'Bitcoin Core version' $DATA_DIR/debug.log | grep -q \"\$(git rev-parse --short=12 {COMMIT})\"; \
      cp $DATA_DIR/debug.log $LOG_DIR/gettxoutsetinfo-{COMMIT}-$(date +%s).log" \
    "./build/bin/bitcoin-cli -datadir=$DATA_DIR -rpcclienttimeout=0 -named gettxoutsetinfo hash_type='none' use_index='false' >/dev/null"

  2d5ab09f0d Merge bitcoin/bitcoin#35124: bench: fix benchmark fixtures and setup checks
  cb63e158d9 walletdb: reuse batch scratch streams

  2026-04-24 | gettxoutsetinfo | i9-ssd | x86_64 | Intel(R) Core(TM) i9-9900K CPU @ 3.60GHz | 16 cores | 62Gi RAM | xfs | SSD

  Benchmark 1: ./build/bin/bitcoin-cli -datadir=/mnt/my_storage/BitcoinData -rpcclienttimeout=0 -named gettxoutsetinfo hash_type='none' use_index='false' >/dev/null (COMMIT = 2d5ab09f0dca4bfec0b365f5f431def2c0c9d70f)
    Time (mean ± σ):     60.063 s ±  1.623 s    [User: 0.001 s, System: 0.002 s]
    Range (min … max):   59.020 s … 61.933 s    3 runs

  Benchmark 2: ./build/bin/bitcoin-cli -datadir=/mnt/my_storage/BitcoinData -rpcclienttimeout=0 -named gettxoutsetinfo hash_type='none' use_index='false' >/dev/null (COMMIT = cb63e158d9ae8276dbe54bba0b0cf8f35378ec71)
    Time (mean ± σ):     56.853 s ±  0.179 s    [User: 0.002 s, System: 0.001 s]
    Range (min … max):   56.675 s … 57.033 s    3 runs

  Relative speed comparison
          1.06 ±  0.03  ./build/bin/bitcoin-cli -datadir=/mnt/my_storage/BitcoinData -rpcclienttimeout=0 -named gettxoutsetinfo hash_type='none' use_index='false' >/dev/null (COMMIT = 2d5ab09f0dca4bfec0b365f5f431def2c0c9d70f)
          1.00          ./build/bin/bitcoin-cli -datadir=/mnt/my_storage/BitcoinData -rpcclienttimeout=0 -named gettxoutsetinfo hash_type='none' use_index='false' >/dev/null (COMMIT = cb63e158d9ae8276dbe54bba0b0cf8f35378ec71)
  ```

  </details>

ACKs for top commit:
  andrewtoth:
    re-ACK 032223f403d320c3c47c7d5932e333f306efcdc3
  CruzMolina:
    tACK 032223f403d320c3c47c7d5932e333f306efcdc3
  achow101:
    ACK 032223f403d320c3c47c7d5932e333f306efcdc3
  optout21:
    ACK 032223f403d320c3c47c7d5932e333f306efcdc3
  sedited:
    ACK 032223f403d320c3c47c7d5932e333f306efcdc3

Tree-SHA512: 6ed51d1a492ca216108b10c01668b01f986260641714951da1d282f1dacf87f0df2b312108f24c06151d3b81eaa4ca6eb4e9ab4e2d829346b0e8f07d0c569a1e
(cherry picked from commit a145fa881a2705a7bed4fe9c6dad589eb1a238d1)

801d36f55b6d421f26d2376327699a04bd22e602 fuzz: use ImmediateBackgroundTaskRunner to silence DEBUG_LOCKORDER (Eugene Siegel)

Pull request description:

  DEBUG_LOCKORDER was reporting a false positive deadlock with the cmpctblock fuzz harness when using ImmediateTaskRunner. Since it is single-threaded, ImmediateTaskRunner callbacks added LockOrders that could never happen outside of a fuzz test.

  First a block would get connected:
  * LOCK(mempool.cs)
  * BlockConnected (fuzz test runs in same thread)
  * LOCK(m_tx_download_mutex)

  Then a later iteration of the LIMITED_WHILE would send a TX:
  * LOCK(m_tx_download_mutex)
  * LOCK(mempool.cs)

  causing a false positive deadlock. Normally, the BlockConnected callback would run in a different thread and no deadlock is reported.

  Fix this by launching a thread that runs the callback and is immediately joined. I compared this PR to another branch (https://github.com/Crypt-iQ/bitcoin/commit/0028847c6b8b937031228e9a1fce83982976d86e) that uses a ThreadPool and found this PR to be more stable and ~4% quicker.

ACKs for top commit:
  maflcko:
    lgtm ACK 801d36f55b6d421f26d2376327699a04bd22e602
  sedited:
    ACK 801d36f55b6d421f26d2376327699a04bd22e602

Tree-SHA512: 5e1f27354c484a90ffd74a1a11e5fed68d7b38d95c06dd39529217f07d535eb9a5b7befb42b2829d79c52b5eb43542bd1079c81d6eb0e56476352ffe98e0177e
(cherry picked from commit 3cab711d69572431af78b0071fb721496f0241d7)

Daily cherry-pick

Expose a stop() call over the IPC socket so remote clients can
signal the node to begin its shutdown sequence. The bitcoin-node
implementation delegates to startShutdown(); bitcoind leaves the
default no-op since it does not listen for IPC connections.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Replace the RPC with IPC

004a7e3cfbc5b2118536651d2201cf8b72c87736 fuzz: Fix txorphan timeout by limiting block weight (marcofleon)

Pull request description:

  The `EraseForBlock` branch in the `txorphan` harness could produce a block with 1000 transactions in it, each with potentially up to 200,000 inputs, resulting in way too many [map lookups](https://github.com/bitcoin/bitcoin/blob/3cab711d69572431af78b0071fb721496f0241d7/src/node/txorphanage.cpp#L625). This was producing inputs that were taking 2 seconds or longer per iteration, which is too long.

  Fix by only adding transactions to the block up to the block weight limit. This matches production behavior, as `EraseForBlock` is only called on a newly [connected block](https://github.com/bitcoin/bitcoin/blob/3cab711d69572431af78b0071fb721496f0241d7/src/net_processing.cpp#L2090).

ACKs for top commit:
  maflcko:
    lgtm ACK 004a7e3cfbc5b2118536651d2201cf8b72c87736
  instagibbs:
    ACK 004a7e3cfbc5b2118536651d2201cf8b72c87736
  sedited:
    ACK 004a7e3cfbc5b2118536651d2201cf8b72c87736

Tree-SHA512: 465504402358e1bed629104b21e05301139f1590884de21e77d566a45e422eef6d4380c5714692f33f5398e4e299b8c9f84b82f58c56a98e410c5c841184aee5
(cherry picked from commit ddb94fd3e1061c465e425629d6c7d4b292301da5)

8ba5f68b1df99350aa037a644041034cf46842dc refactor, key: move `CreateMuSig2PartialSig` to `musig.{h,cpp}` module (Sebastian Falbesoner)
d087f266fc24145e3a34a9f2e8f08c583f806aad refactor, key: move `CreateMuSig2Nonce` to `musig.{h,cpp}` module (Sebastian Falbesoner)
f36d89f4363a25f7948a0f7096201ef8e15045d8 key: add `GetSecp256k1SignContext` access function (w0xlt)

Pull request description:

  This PR is a follow-up of #29675, see https://github.com/bitcoin/bitcoin/pull/29675#discussion_r2265077463. It moves all MuSig2 functions that currently live in `CKey` and call secp256k1 musig module API functions (i.e. `secp256k1_musig_...`) to the `musig.{h,cpp}` module, as this seems to be a better place. For accessing the `secp256k1_context_signing` object from the outside, a new function `GetSecp256k1SignContext` is added in the third commit.

  As the patch is mostly move-only, it can be best reviewed via the git option `--color-moved=dimmed-zebra`

ACKs for top commit:
  achow101:
    ACK 8ba5f68b1df99350aa037a644041034cf46842dc
  w0xlt:
    reACK 8ba5f68b1df99350aa037a644041034cf46842dc
  rkrux:
    lgtm ACK 8ba5f68b1df99350aa037a644041034cf46842dc
  furszy:
    ACK 8ba5f68b1df99350aa037a644041034cf46842dc

Tree-SHA512: 95fcaa5d7a09037a0dce0053b8c640a7372a1251a2a3615c565f4dacc5aad5cf0ee8bfc43aa0d0def628465c16330d69f6ea9fcc07bbadc971863248f60d1878
(cherry picked from commit 379b9fbf036e2f214c4fce2a1ba086def4abac65)

Daily cherry pick

build, ci: Remove IPC configuration and install `capnp` on runners

This is only used for grinding hashes and is no longer linked anywhere

Remove the `bitcoin-util` executable

This is a CLI for manually manipulating transactions. Nice to have but
seems outside of the scope for maintenance here.

Remove `bitcoin-tx` executable

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Remove Windows CI jobs and helper scripts

8544537f41df568e6e1cb94eeab9e699b9190427 mining: drop unused include_dummy_extranonce option (Sjors Provoost)
58eeab790d9825a777f907e3e912a2da78cbc76d mining: only pad with OP_0 at heights <= 16 (Sjors Provoost)
00d22328b0560bf9773417495123ae68bb89e4d1 mining: pad coinbase to fix createNewBlock at heights <=16 (Sjors Provoost)
605ff37403f0b50c5664bb4e2d6eaf84022d53e4 test: bad-cb-length for createNewBlock() at low heights (Sjors Provoost)
1966621b76885257b4b4e44aab4712e9f84313e6 test: refactor IPC mining test to use script_BIP34_coinbase_height (Sjors Provoost)

Pull request description:

  Blocks 0-16 on any new chain require mining code to be careful not to violate the `bad-cb-length` rule, which states the coinbase transaction scriptSig must be at least 2 bytes.

  Our mining code deals with that by padding the `scriptSig` with a 0 `extraNonce`. It does this for every height. As a result IPC clients would get an unnecessary `0` in the `scriptSigPrefix` field of  `CoinbaseTx`. #32420 fixed that by introducing a `include_dummy_extranonce` option in `BlockCreateOptions` and turning that off for IPC clients.

  A minor issue was missed though: `createNewBlock()` now fails with `bad-cb-length`. An easy workaround is to use the `generate` RPC for the first 16 blocks, as demonstrated in the 2nd commit.

  The real fix is to have the miner code always pad the `scriptSig` at lower heights, but to _not_ include that in the `scriptSigPrefix` field of  `CoinbaseTx` (introduced in #33819). This is what the 3rd commit implements.

  Now that we set `scriptSigPrefix` independent of what our internal miner code does - to get past `CheckBlock()` - the original motivation for `include_dummy_extranonce` goes away and we can just drop it entirely. The last commit drops it, while the 4th commit adjusts the tests and hardcoded block and assume utxo hashes.

  This last change does not break IPC clients, because `include_dummy_extranonce` was never exposed in `mining.capnp`.

  Instead of adjusting the hardcoded hashes, an alternative approach would be to just always pad the `scriptSig` internally, since we exclude the padding from `scriptSigPrefix` anyway. However, IPC clients can also call `getBlock()` to get the raw block and might be confused about the difference. The miner code is also easier to understand if we limit the exception (`coinbase_tx.script_sig_prefix != coinbaseTx.vin[0].scriptSig`) to `nHeight <= 16`, where the explanation is based purely on consensus rules rather than historical test suite reasons.

  The first two commits are preperation test changes:
  -  extract `assert_capnp_failed` helper for macOS (also part of #34727)
  -  use `script_BIP34_coinbase_height` in IPC mining test (existing code in `interface_ipc_mining.py` was incorrect for low height

  Fixes #35126

ACKs for top commit:
  ryanofsky:
    Code review ACK 8544537f41df568e6e1cb94eeab9e699b9190427. Just rebased to fix silent conflict and applied some minor suggestions since last review. As part of rereviewing I left some more minor suggestions that are fine to ignore.
  sedited:
    Re-ACK 8544537f41df568e6e1cb94eeab9e699b9190427

Tree-SHA512: a01d48842bf4bcc1a9c51a89ef9d750766db7d04edb4dcd6b3a8bf195c6b4fa07445256a49367ff0db00ab489a52a3d7ff6a5c3ab9290ecb1fcb82f532552e9b
(cherry picked from commit 7802e578c3f1e9a5d9b57fb003349d0e032bb43b)

Daily cherry pick

b6c367044288f83ab61c1a77ad34c33adf39ecf6 i2p: clean up SAM error logging (takeshikurosawaa)

Pull request description:

  Clean up the I2P SAM error path.

  `SESSION CREATE` may contain the private key, so the generic SAM reply
  error path now reports the redacted request text instead of the full
  request. It also avoids echoing raw router replies in those generic
  error messages.

  No network behavior change intended.

ACKs for top commit:
  davidgumberg:
    crACK https://github.com/bitcoin/bitcoin/pull/35117/commits/b6c367044288f83ab61c1a77ad34c33adf39ecf6
  vasild:
    ACK b6c367044288f83ab61c1a77ad34c33adf39ecf6

Tree-SHA512: 204c8b64c6d3dd2f94f92cdc6d3daefd7773c42066984b9da859ebc2912c2ed38079d9e82a2d1f09d8d720750047114a80189e688929d7a0af5da2c2ee4a88da
(cherry picked from commit b2a3ca3df901dcc19b07f7dcf3115d8f7835b931)

371eac8069a47f27c3c388c7cb2251f0a2a1d8e8 fuzz: exercise ForNode/ForEachNode callbacks in connman fuzz harness (frankomosh)

Pull request description:

  Track inserted node IDs and sometimes reuse them in `ForNode()` so the successful lookup path is exercised more reliably. Replace no-op callbacks with lightweight CNode accessor calls to make `ForEachNode()` and `ForNode()` cover previously unreached callback code paths.

  This addresses feedback from https://github.com/bitcoin/bitcoin/pull/34830#issuecomment-4074732710  where it was noted that the callbacks had "neither the return type checked nor its side-effect”.

  Coverage reports from the connman fuzz corpus, before and after the change:

  - [Before](https://frankomosh.github.io/fuzz-coverage/connman-callback-coverage/before/index.html)
  - [After](https://frankomosh.github.io/fuzz-coverage/connman-callback-coverage/after/index.html)

  `diff cov_show_before.txt cov_show_after.txt` filtered to `ForNode`/`ForEachNode`/`IsFullOutboundConn`/`ConnectionTypeAsString`:

  **`IsFullOutboundConn` — `net.h:786-788`**
  ```diff
  -  786|      0|    bool IsFullOutboundConn() const {
  -  787|      0|        return m_conn_type == ConnectionType::OUTBOUND_FULL_RELAY;
  -  788|      0|    }
  +  786|  1.13M|    bool IsFullOutboundConn() const {
  +  787|  1.13M|        return m_conn_type == ConnectionType::OUTBOUND_FULL_RELAY;
  +  788|  1.13M|    }
  ```

  **`ConnectionTypeAsString` — `net.h:967`**
  ```diff
  -  967|      0|    std::string ConnectionTypeAsString() const { return ::ConnectionTypeAsString(m_conn_type); }
  +  967|  1.11M|    std::string ConnectionTypeAsString() const { return ::ConnectionTypeAsString(m_conn_type); }
  ```

  **`ForNode` — `net.cpp:4126-4131`**
  ```diff
  -  4126|  1.08k|        if(pnode->GetId() == id) {
  -    |  Branch (4126:12): [True: 0, False: 1.08k]
  -  4127|      0|            found = pnode;
  -  4131|     39|    return found != nullptr && NodeFullyConnected(found) && func(found);
  -                                              ^0                          ^0
  +  4126|    602|        if(pnode->GetId() == id) {
  +    |  Branch (4126:12): [True: 1, False: 601]
  +  4127|      1|            found = pnode;
  +  4131|     28|    return found != nullptr && NodeFullyConnected(found) && func(found);
  +                                              ^1                          ^1
  ```

  **`ForEachNode` — `net.h:1270-1271`**
  ```diff
  -  1270|  1.13M|            if (NodeFullyConnected(node))
  -    |  Branch (1270:17): [True: 0, False: 1.13M]
  -  1271|      0|                func(node);
  +  1270|  1.11M|            if (NodeFullyConnected(node))
  +    |  Branch (1270:17): [True: 1.11M, False: 0]
  +  1271|  1.11M|                func(node);
  ```

  Two previously uncovered functions (`IsFullOutboundConn`, `ConnectionTypeAsString`) are now exercised through the iteration callbacks. `ForNode` finds matching nodes.

ACKs for top commit:
  nervana21:
    tACK 371eac8069a47f27c3c388c7cb2251f0a2a1d8e8
  maflcko:
    lgtm ACK 371eac8069a47f27c3c388c7cb2251f0a2a1d8e8

Tree-SHA512: 3587c021b16e38ca252676a21b66c5383ab2bd3eec9073e61e9a93db7ef84a94ce5a0c037ac512483680cafabb44103b86df0893e8a9b1bf63b8383bd54f4641
(cherry picked from commit 278b9e39df2d7298fadf88f76607463005b6eb3c)