Classify outputs and amounts for SCBForceCloseChannel

[ziggie1984]

We also log the amounts to the user so they know whether it is worth taking the risk publishing a potential outdated transaction.

[Copilot]

Pull Request Overview

This PR adds output classification functionality to the scbforceclose command, which helps users identify different types of outputs (to_remote, anchors, to_local/htlc) in force-close transactions derived from static channel backups (SCBs).

• Adds logic to classify transaction outputs by matching against known script templates
• Maps SCB backup versions to channel types for proper script derivation
• Includes a test with real-world transaction data to verify the classification logic

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
cmd/chantools/scbforceclose.go	Adds classifyOutputs, classifyAndLogOutputs, and chanTypeFromBackupVersion functions to identify and log different output types in force-close transactions
cmd/chantools/scbforceclose_test.go	Adds test case with real-world data to verify to_remote output identification across different channel versions and initiator roles

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[starius]

LGTM! 💾
The code looks correct, but needs some shaving.
I tested the binary with my real backup and it works correctly.
Thanks for this improvement!

[starius]

Idea, if you like it:

case chanbackup.AnchorsCommitVersion:
		chanType = channeldb.AnchorOutputsBit
		chanType |= channeldb.SingleFunderTweaklessBit
		fallthrough

case chanbackup.AnchorsZeroFeeHtlcTxCommitVersion:
		chanType |= channeldb.ZeroHtlcTxFeeBit

Also SimpleTaprootVersion and SimpleTaprootVersion can be coupled.

[ziggie1984]

are you sure they can be couple because the version check for every backup version is different ?

For AnchorsZeroFeeHtlcTxCommitVersion we won't enter the AnchorsCommitVersion case or don't I understand your proposal here ?

[guggero]

Thanks a lot, this is great!

I added a --channel_point flag that allows to force close a single channel when specifying a multi backup file.
Also added an integration test for the command.