Replace the unreliable Gitea wiki API with direct Git operations:
- Clone {repo}.wiki.git, copy docs with link transformation, push
- Faster: single git push vs N API calls
- More reliable: no API timeouts or rate limits
- Atomic: all pages sync in one commit
- Auto-pruning: stale wiki pages removed automatically
- Link transformation: [text](file.md) → [text](file) for wiki format
- 36 new tests covering transform_links, clone, sync_files, commit, verify
Generated with [Devin](https://devin.ai)
Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>
