parallelize FFI language binding tests in contrib/test.sh

[caarloshenriq]

Parallelizes the language binding tests in payjoin-ffi/contrib/test.sh
instead of running them sequentially.

This is a follow-up to a comment by @spacebear21 on #1492.

AI Assistance: Used Claude to help implement the parallelization approach.

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[coveralls]

Coverage Report for CI Build 25011520047

Coverage remained the same at 84.989%

Details

• Coverage remained the same as the base build.
• Patch coverage: No coverable lines changed in this PR.
• No coverage regressions found.

Uncovered Changes

No uncovered changes found.

Coverage Regressions

No coverage regressions found.

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Coverage Stats

Relevant Lines:	13437
Covered Lines:	11420
Line Coverage:	84.99%
Coverage Strength:	398.84 hits per line

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💛 - Coveralls

[benalleng]

Added a commit to fix the execution permissions which were a problem in JS too.

TACK 8b64a29

[benalleng]

So I have it in writing I did have to clean the ~/payjoin-ffi/dart/native/Cargo.lock as it was suffering from a failure due to the stuff from #1502. Maybe it would be useful to have a script to just clean this deep nested lockfile every time we run tests assuming it doesn't get touched very often.

[caarloshenriq]

Maybe it would be useful to have a script to just clean this

added a script in dart/contrib/test.sh to clean this.

[spacebear21]

cACK

I'm afk this week so may not get around to testing this but ideally would like someone to validate and post the output of:

• all succeeds
• fails for one specific language
• fails for all languages