- Add Count function to deletions package for fast line counting
- Add maybeAutoCompactDeletions to sync (opt-in via deletions.auto_compact config)
- Fix regex escaping in batchCheckGitHistory (bd-bgs)
- Add 30s timeout to git history commands (bd-f0n)
- Use git rev-parse --show-toplevel for proper repo root detection (bd-bhd)
- Add tests for Count and auto-compact functionality
Closes: bd-qsm, bd-bgs, bd-f0n, bd-bhd