GTAGPT Mobile Demo v4A — Rooftop & Collision Test

Open mobile_demo_v4a.html on iPhone/Safari.

New in v4A:
- Hand-authored non-grid city structure.
- Water canal + bridge.
- Roof blocks are solid.
- Trees are solid.
- Water is solid.
- Alley/sidewalk/road walkability and drivability are separated.
- Parked/random cars retained.
- Pedestrians prefer walkable sidewalk/park/bridge/alley tiles.
- Vehicle collision damage remains.
- Mobile controls preserved.

Controls:
- Left touch joystick: move / drive
- ENTER: enter / exit nearest car
- BOOST: speed boost while driving
