docs: CLAUDE.md has stale references and missing context

## Problem

`.claude/CLAUDE.md` has references to files/ADRs that are inconsistent with the current repo state.

## Issues Found

### 1. ADR-006 Reference is Misleading
```markdown
- `check-version-increment: false` in ct.yaml/ct-install.yaml
- See [ADR-006](../docs/src/adr/006-release-please-versioning.md) for details
```

ADR-006 is marked as **superseded** by ADR-003 in the actual ADR file, but CLAUDE.md presents it as the current approach.

**Reality**: We use git-cliff + version-bump.sh (ADR-003), not release-please.

### 2. Missing Key Workflow Information
CLAUDE.md should include:
- Brief description of W1, W2, W5, W6 workflow pipeline
- Information about the atomic branching model
- Reference to auto-merge workflow for integration

### 3. Labels Strategy Reference
References `memory/repo-labels.md` which exists in `.claude/memory/repo-labels.md` - path should be relative.

## Recommended Changes

1. Remove or clarify ADR-006 reference - point to ADR-003 instead
2. Add "Workflow Pipeline" section with brief overview
3. Fix relative path for labels strategy
4. Add reference to ADR-011 (Full Atomization Model)

## Related
- Part of documentation refresh for chart release workflows