- Created grid overlay utility (apps/web/src/utils/gridOverlay.ts) for dev mode
- Toggle with Ctrl+G (Cmd+G on Mac) keyboard shortcut
- Shows 8px grid overlay to visualize spacing alignment
- Only works in development mode (import.meta.env.DEV)
- Initialized in main.tsx after app setup
- Action 11.2.1.4: Add visual grid overlay tool (dev only) - COMPLETE
