fix: Symlink .auto-build-data/ and .claude/rules/ in worktrees

Worktrees now have symlinks to the main repo's:
- .auto-build-data/ - specs, plans, status, memory
- .claude/rules/ - auto-build patterns and learned memory

This ensures /ab:build can detect PLANNING_COMPLETE status when
running in worktree and continue with implementation.

Also clarified in build.md that PLANNING_COMPLETE skips planning.

Bumps version to 1.0.5.

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

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

plugin/commands/build.md

@@ -71,7 +71,11 @@ To work in the isolated worktree, you need a new session there.
 
 ### 3. Planning Phase
 
-If status is `SPEC_COMPLETE`:
+**If status is `PLANNING_COMPLETE`** (plan already exists):
+- Skip directly to Implementation Loop (step 4)
+- This happens when resuming in a worktree after plan was created in main repo
+
+**If status is `SPEC_COMPLETE`**:
 
 1. Load memory context (if exists):
    - Read `.auto-build-data/memory/patterns.json`