Consume self in Monitor check_for_transaction

[xstoicunicornx]

Take the receiver by value instead of by reference so the state machine no longer needs internal clones to construct transient and stasis transitions. Callers get the current state back through Stasis outcomes or transient errors, matching the pattern used by the other receiver transitions.

Update the CLI monitoring loop to rebind the state from Stasis and transient-error outcomes instead of reusing a borrowed receiver, and clone the monitor in the typestate unit test where it is exercised multiple times.

This comes out of a suggested update from #1724 (comment).

Claude Fable was used to help make these edits.

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[coveralls]

Coverage Report for CI Build 29125172829

Coverage increased (+0.004%) to 86.014%

Details

• Coverage increased (+0.004%) from the base build.
• Patch coverage: 8 uncovered changes across 2 files (8 of 16 lines covered, 50.0%).
• No coverage regressions found.

Uncovered Changes

File	Changed	Covered	%
payjoin-cli/src/app/v2/mod.rs	9	4	44.44%
payjoin/src/core/receive/v2/mod.rs	7	4	57.14%

Coverage Regressions

No coverage regressions found.

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Coverage Stats

Relevant Lines:	15880
Covered Lines:	13659
Line Coverage:	86.01%
Coverage Strength:	343.67 hits per line

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💛 - Coveralls

[spacebear21]

concept ACK - check_for_transaction is a bit of an awkward method currently but this seems worth it for the consistency win until #1692 is revisted.