- Add comprehensive documentation for local manifest feature
- Create example local-manifest.json with custom playbook structure
- Implement local manifest reading and merging with official manifests
- Add file watcher for hot reload on local manifest changes
- Support local filesystem paths (absolute and tilde-prefixed)
- Add "Local" badge to distinguish custom playbooks in UI
- Expose manifest change event through preload API
- Add source field to playbook type for origin tracking
