- Settings layout with sidebar nav (Profile, MCP Server, Users)
- Profile page: display name, email, password, sessions
- MCP page: API key CRUD, JSON config with copy button, LLM prompt
- Config auto-populates with actual API key when one is created
- Remove duplicate Settings link from sidebar
- Users page integrated into settings nav (admin only)
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>