Prune and fix CI test suites

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 #5561 merged (0393fc594; Jaah Deploy green). Fixed the 6 smoke specs red on every test.yml run and 5 flakes (2 real web bugs); pruned 10 tests; quick tier 27→23s. Not verified: a post-merge test.yml run (no promotion PR is open; opening one is human-gated). Full gate green.