feat: Move specs and memory to git for multi-developer collaboration (v1.0.6)

BREAKING CHANGE: Specs, plans, and memory moved from .auto-build-data/ (gitignored)
to .auto-build/ (git-tracked) to enable team collaboration.

Changes:
- Specs/plans now in .auto-build/specs/ (shared with team)
- Memory (patterns, gotchas) now in .auto-build/memory/ (shared with team)
- .auto-build-data/ now only contains local data (worktrees, cache)
- Added /ab:migrate command for existing projects
- Removed symlinks from worktree-create.sh (no longer needed)

Benefits:
- Any developer can continue a plan started by another
- Patterns and gotchas shared across team
- Works on Windows/Linux/Mac without symlinks
- Full version history in git

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

plugin/.claude-plugin/plugin.json

@@ -1,7 +1,7 @@
 {
   "name": "ab",
   "description": "Auto-Build: Spec-driven build orchestration with worktree isolation and session memory",
-  "version": "1.0.5",
+  "version": "1.0.6",
   "author": {
     "name": "ROA2WEB Team"
   }