v0.57.5: Opus 4.6, semantic diffs, npm package, plugin hooks, and startup optimizations

New features

- Claude Opus 4.6 - Added Claude Opus 4.6 model support
- Semantic structured diffs - Code change diffs now use semantic structure-aware rendering for better readability
- Plugin hooks - Added support for plugin hooks with Claude hooks format compatibility
- npm package - CLI is now installable via npm: npm install -g droid
- User-invocable skills as slash commands - Custom skills marked as user-invocable are now registered as slash commands
- FACTORY_LOG_FILE and FACTORY_DISABLE_KEYRING env vars - New environment variables for log file output and keyring control
- Enterprise Controls - New settings page for managing agent behavior, command policy, model access, and security (Factory App)
- Skills UI - Skills button and modal added to the chat input for easy skill access (Factory App)
- Ask User tool - Ask User tool now available in the web and Factory App surfaces

Improvements

- Startup latency - Optimized CLI startup with sub-metric tracking for faster launch times

Bug fixes

- Unicode crash - Fixed CLI crash when sessions contain certain unicode characters
- Marketplace auto-update - Auto-update now only runs in interactive mode, not during droid exec