Reject unknown matrix badge statuses

[maxi-maxima]

Summary

• make matrix badge generation reject unknown status tokens instead of coercing them to failing
• make matrix marker aggregation reject malformed or unknown statuses
• add regression tests for unknown and malformed status inputs

Closes #26.

Validation

• python -m unittest discover -s test -p "*matrix*_test.py"
• git diff --check

Generated with DevLoop-style issue diagnosis and manually reviewed before opening.

[monsieurleberre]

Reviewed aggressively as our first outside contribution: line-by-line diff audit, hidden-unicode scan, tree/mode verification vs merge-base, full data-flow trace (job.status → markers → aggregate → write-badges.sh), adversarial injection testing of the error paths, and consumer-repo impact check (canton-ledger-api-csharp, daml-codegen-csharp — both feed pure JSON booleans, zero breakage). 52/52 tests pass locally and CI is green. Implements #26 exactly as specified. LGTM.

[monsieurleberre]

Thank you, DevLoop 🤖 Exactly what #26 asked for, regression tests included — we are merging this! 🎉

A quick peek at your GitHub profile suggests you never sleep... 113 repos and counting 😄 Glad this repo made the tour — come back any time! 🤝

In fact, standing invitation: if you feel like a second round, grab any small open issue on peacefulstudio/daml-codegen-csharp or peacefulstudio/canton-ledger-api-csharp — whichever catches your eye — and send a PR. We'd genuinely welcome it 🚀

[monsieurleberre]

Thank you, DevLoop 🤖 Exactly what #26 asked for, regression tests included — merged! 🎉

A quick peek at your GitHub profile suggests you never sleep... 113 repos and counting 😄 Glad this repo made the tour — come back any time! 🤝

In fact, standing invitation: if you feel like a second round, grab any small open issue on peacefulstudio/daml-codegen-csharp or peacefulstudio/canton-ledger-api-csharp — whichever catches your eye — and send a PR. We'd genuinely welcome it 🚀