Updated multiple agents to understand and properly handle TDD (Test-Driven
Development) tags as documented in CONTRIBUTING.md. This prevents confusion
when agents encounter tests with @tdd_expected_fail that invert their behavior.
Key changes:
- Test writers (behave-tester, robot-tester) now understand when to use TDD tags
- Implementers know to remove @tdd_expected_fail tags when fixing bugs
- Test-fixer won't try to "fix" correctly passing TDD tests
- PR reviewers check for proper TDD tag removal in bug fix PRs
- Human liaison can explain TDD tags to confused developers
- Coverage improver avoids modifying TDD tests
- Reference reader includes TDD tag info in summaries
This ensures all agents work correctly with the TDD workflow where tests are
written before bug fixes and use special tags to prove bugs exist.