GitHub Actions test cleanup and fixes

Review all test suites, delete stale, superseeded, those that were one off to check feature flags or absence of something. Kill the most long running or flaky with unit tests that execute in milliseconds. Regroup between quick and full, Fix broken tests in CI - GitHub Actions - look at a few recent test runs and fix broken/flaky tests. Babysit CI/CD until the tests (test.yaml) pass.

PR #4890 merged: fixed outbox alarm CI flake (induction-proven), Event catalog selftest ~9.5s→2.9s, removed unsupported-width arms + retired 0404/0405 migration tests, added unit halves. Full gate green; Jaah Deploy + develop Tests green.