refactor: `wallet_importdescriptors` to separate `run_test()` contents into specific functions #36402

The motivation behind this PR came when reviewing a PR related with wallet_importdescriptors and I noticed that the run_test() function was more than 800 lines of code long, and looked messy and confusing, specially for someone not familiar with that test suite. I believe refactoring the contents inside run_test() and separating it into specific functions would make the test easier to understand and to add new future test cases.

To review this PR, I recommend using the following command to easily see that the changes are only code movement and function organization:

git show --color-moved=dimmed-zebra

Suggestions about the new functions, organization, or their order are more than welcome. The approach I took is the one I felt would provide a good balance between keeping the code clean and making the changes as easy as possible to review.

If reviewers would prefer to split this into multiple commits, I'm also happy to do so.

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The following sections might be updated with supplementary metadata relevant to reviewers and maintainers.

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External sites

• Code coverage & benchmarks: https://corecheck.dev/bitcoin/bitcoin/pulls/36402
• Ralph review <img src=https://review.fish.foo/assets/bitcoin/bitcoin/36402.png alt="Ralph review status"> https://git.fish.foo/bitcoin/bitcoin/pulls/36402#author-ralph

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Reviews

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Conflicts

Reviewers, this pull request conflicts with the following ones:

• #36257 _{<img src="https://drahtbot.space/ack_count/bitcoin/bitcoin/36257.svg">} (qa: assert_equals -> assert_true/assert_false by hodlinator)
• #31668 _{<img src="https://drahtbot.space/ack_count/bitcoin/bitcoin/31668.svg">} (Added rescan option for import descriptors by saikiran57)

If you consider this pull request important, please also help to review the conflicting pull requests. Ideally, start with the one that should be merged first.

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LLM Linter (✨ experimental)

Possible places where named args for integral literals may be used (e.g. func(x, /*named_arg=*/0) in C++, and func(x, named_arg=0) in Python):

• test/functional/wallet_importdescriptors.py: multi_priv_big.sendtoaddress(w0.getnewaddress(), 10, "", "", True)

^{2026-10-09 12:19:54}

Approach aCK

Concept ACK

There are some unnecessary new lines added and removed that add noise to the color-dimmed filter :)

Concept ACK

There are some unnecessary new lines added and removed that add noise to the color-dimmed filter :)

I've tried to avoid them as much as possible, but some of them are necessary to re-arrange into new functions keeping the separations of the original tests intact.

Rebased on master