Two Test Lanes Cleanup

Goal

Collapse the repo test model to exactly two lanes:

• fast: *.spec.ts[x]
• slow: *.slow.ts[x]

Why

The current setup has a hidden path-bucketed slow lane in test-fast.mjs on top of the explicit *.slow.* lane. That makes docx and package-integration tests behave like slow tests without actually being named or run like slow tests.

Work

1. Remove path-based slow buckets from tooling/config/test-suites.mjs.
2. Update fast-lane tooling to stop excluding files by path.
3. Rename current bucketed slow specs to *.slow.ts[x]:
   • packages/docx/src/**
   • packages/docx-io/src/**
   • apps/www/src/__tests__/package-integration/**
   • the current reactHeavy specs
4. Keep test:slow as the single slow-lane runner.
5. Update active testing guidance so “slow” means filename suffix only.