When bd init runs in a forked repo (detected via upstream remote), prompt
the user to configure .git/info/exclude to keep beads files local.
- Add --setup-exclude flag for manual trigger
- Add fork detection to init flow (reuses detectForkSetup)
- Add setupForkExclude() to configure .git/info/exclude with:
.beads/, **/RECOVERY*.md, **/SESSION*.md
- Add promptForkExclude() with Y/n prompt (default yes)
- Add containsExactPattern() helper for precise pattern matching
🤖 Generated with Claude Code
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>