refactor: move embedded patterns from agents to skills (#174)
Reduces the 6 largest agent prompts by 79-87%, saving ~2,800 lines
that loaded into subagent context on every invocation.
Changes:
- e2e-runner.md: 797 → 107 lines (-87%)
- database-reviewer.md: 654 → 91 lines (-86%)
- security-reviewer.md: 545 → 108 lines (-80%)
- build-error-resolver.md: 532 → 114 lines (-79%)
- doc-updater.md: 452 → 107 lines (-76%)
- python-reviewer.md: 469 → 98 lines (-79%)
Patterns moved to on-demand skills (loaded only when referenced):
- New: skills/e2e-testing/SKILL.md (Playwright patterns, POM, CI/CD)
- Existing: postgres-patterns, security-review, python-patterns
Affaan Mustafa