Added a settings panel with sliders for:
- **Thrust Power** (500-10000)
- **Pitch/Roll/Yaw Sensitivity**
- **Lift Coefficient**
- **Gravity**
- **Linear/Angular Damping**
- **Start Altitude** (now defaults to 15000m - 50x higher)

All settings update in real-time. Press Space to reset with the new altitude. Tweak away!