Dialog for allowing the user to choose the change output when bumping a tx

[achow101]

Based on https://github.com/bitcoin/bitcoin/pull/26467

Implements a GUI dialog for allowing the user to choose the output to reduce when bumping a transaction. This adds the functionality that was added to the RPC.

[DrahtBot]

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Reviews

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Type	Reviewers
Concept ACK	luke-jr
Approach ACK	john-moffett, w0xlt

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Conflicts

No conflicts as of last run.

[Sjors]

Can you add a screenshot to the PR description (and one for the single-output case)?

[Sjors]

Can we be a bit more bold and just assume that a change address is change, and not show the dialog in that case? Ideally we don't show such a dialog more often than necessary.

[john-moffett]

That would prevent the case where you wanted to deduct the extra fee from the recipient, such as when you initially selected "Subtract fee from amount".

Ideally, you'd only show the dialog if that were selected previously, but I don't think it's persisted anywhere. Eg -

https://github.com/bitcoin-core/gui/blob/30f553d45797847166109a161628dba3bf00bc94/src/qt/sendcoinsrecipient.h#L42

I could be wrong, though.

[luke-jr]

Concept ACK. I'd just show "Change" for the change, though. End users shouldn't need to know about change addresses.

[achow101]

Rebased and fixed the build issue in the first commit.

[hebasto]

test_bitcoin-qt fails in the CI: https://github.com/bitcoin-core/gui/actions/runs/11186485220.

[DrahtBot]

🚧 At least one of the CI tasks failed. _{Task previous releases, depends DEBUG: https://github.com/bitcoin-core/gui/runs/31101606803 LLM reason (✨ experimental): The CI failure is due to a build error in bumpfeechoosechangedialog.cpp.}

Hints

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[achow101]

Are you still working on this?