Persister no longer treats transient errors as errors in MaybeTerminalSuccessTransition

[benalleng]

Closes #1709

Previously a transient error was treated as an error in the persister alongside fatal errors but unlike fatal errors transient errors were not giving the state at which it was reached.

This commit returns the current state alongside the error while still retaining a NoOp in the persister with the expectation that the caller will want to try again.

Coded with assistance from deepseek v4

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[coveralls]

Coverage Report for CI Build 29046681515

Coverage decreased (-0.07%) to 85.932%

Details

• Coverage decreased (-0.07%) from the base build.
• Patch coverage: 38 uncovered changes across 3 files (51 of 89 lines covered, 57.3%).
• 2 coverage regressions across 2 files.

Uncovered Changes

File	Changed	Covered	%
payjoin-cli/src/app/v2/mod.rs	32	0	0.0%
payjoin/src/core/persist.rs	38	34	89.47%
payjoin/src/core/receive/v2/mod.rs	19	17	89.47%

Coverage Regressions

2 previously-covered lines in 2 files lost coverage.

File	Lines Losing Coverage	Coverage
payjoin-cli/src/app/v2/mod.rs	1	51.59%
payjoin/src/core/persist.rs	1	95.9%

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Coverage Stats

Relevant Lines:	15695
Covered Lines:	13487
Line Coverage:	85.93%
Coverage Strength:	347.63 hits per line

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💛 - Coveralls

[xstoicunicornx]

I think it is creating a bit of an anti pattern - namely that for this transition the transient error is considered a success while for all other transitions the transient error is still an error. Was there a reason you feel like for this transition it should be a success rather than an error?

[benalleng]

This serves as a blueprint for the transition states. If we feel like we like this shape I can implement the rest the same way

[spacebear21]

I had Fable write an alternative, more generic approach for the same concept here #1724. The first commit is the relevant one, introducing current state on all transient errors.

[spacebear21]

Superseded by #1724