Test Suite Cleanup and CI Fix

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 #5442 merged and deployed. Pruned ~20 stale guards. Fixed the wizard race behind a smoke flake, plus 2 more flakes. CI red was tf fmt (fixed by 6286). Local smoke had been skipped. No promotion PR open to re-run test.yml. Deferred: smoke harness check, local tf fmt, wizard UI polish.