Skip taproot coins in payjoin-cli

[benalleng]

I found this bug when testing payjoins in liana where a taproot coin would be added to my payjoin-cli wallet and then the next time I would try to do a payjoin the latest utxo would be a taproot output and would then cause errors when trying to do a payjoin.

This PR simply skips taproot outputs as coins to be chosen in the payjoin-cli.

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[coveralls]

Coverage Report for CI Build 26908339625

Coverage increased (+0.005%) to 85.363%

Details

• Coverage increased (+0.005%) from the base build.
• Patch coverage: 6 of 6 lines across 1 file are fully covered (100%).
• No coverage regressions found.

Uncovered Changes

No uncovered changes found.

Coverage Regressions

No coverage regressions found.

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Coverage Stats

Relevant Lines:	13862
Covered Lines:	11833
Line Coverage:	85.36%
Coverage Strength:	392.03 hits per line

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💛 - Coveralls

[zealsham]

tACK.

i loaded a wallet with only P2tr as UTXO for sender and then repeated for receiver
aswell . payjoin-cli skipped those utxos

Error: No spendable UTXOs available in wallet. Please ensure your wallet has confirmed funds.

[DanGould]

I found this bug when testing payjoins in liana where a taproot coin would be added to my payjoin-cli wallet and then the next time I would try to do a payjoin the latest utxo would be a taproot output and would then cause errors when trying to do a payjoin.

What kind of errors? I'm not totally convinced "we shouldn't support any of the state of the art outputs" is the path forward here yet. Are these tapscripts that can't be satisfied or something? Seems like more of a wallet hygiene problem than a payjoin-cli problem but the details are incomplete