doc: update CWallet::SignTransaction doc to mention SIGHASH_DEFAULT #32411

1. 
   rkrux commented at 8:21 AM on May 3, 2025: contributor

   While SIGHASH_DEFAULT & SIGHASH_ALL are effectively the same, it's helpful to mention in the function doc exactly what's present in the code.

   It can be seen in the function implementation that SIGHASH_DEFAULT is passed to the overloaded SignTransaction function.

   Ref: https://github.com/bitcoin/bitcoin/blob/f490f5562d4b20857ef8d042c050763795fd43da/src/wallet/wallet.cpp#L2177-L2194

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2. doc: update CWallet::SignTransaction doc to mention SIGHASH_DEFAULT

   While `SIGHASH_DEFAULT` & `SIGHASH_ALL` are effectively the same,
   it's helpful to mention in the function doc exactly what's present
   in the code.
   
   It can be seen in the function implementation that `SIGHASH_DEFAULT`
   is passed to the overloaded `SignTransaction` function.
   
   Ref: https://github.com/bitcoin/bitcoin/blob/f490f5562d4b20857ef8d042c050763795fd43da/src/wallet/wallet.cpp#L2177-L2194

   11ff4c9641
3. 
   DrahtBot commented at 8:21 AM on May 3, 2025: contributor

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   For details see: https://corecheck.dev/bitcoin/bitcoin/pulls/32411.

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4. DrahtBot added the label Docs on May 3, 2025
5. fanquake requested review from Sjors on May 13, 2025
6. 
   Sjors commented at 11:49 AM on May 13, 2025: member

   They're only the same for Taproot inputs.

   cc @achow101

7. 
   achow101 commented at 5:34 PM on May 13, 2025: member

   DEFAULT and ALL are effectively the same for Taproot inputs, and DEFAULT is an alias for ALL for non-taproot inputs. I don't think that this change is meaningfully useful as ALL and DEFAULT are essentially aliases for each other, and mean basically the same thing.

8. 
   rkrux commented at 5:49 PM on May 13, 2025: contributor

   True. The main reason for this change was that I didn't see any benefit in leaving ALL around in the function documentation when the implementation uses DEFAULT.

   I am open to closing this PR later if this doesn't seem like a strong enough reason.

9. rkrux closed this on May 26, 2025

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Review Requested
Sjors