Add to shared package:
- Git status styles (dirty/ahead/behind/clean/conflict)
- CheckMark() helper for presence indicators (✓/—)
- Label() helper for key-value labels
- CheckResult() helper for environment check output
Update packages to use new shared utilities:
- cmd/dev: use shared git styles for table cells
- cmd/docs: use CheckMark() and Label() helpers
- cmd/doctor: use CheckResult() and Success()/Error() helpers
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>