Added a driving dashboard and Shift boost

I added a vehicle dashboard with live speed, gear and fuel readings. Holding Shift applies a temporary driving boost, making the state visible both in the vehicle movement and its gauges.

The boost increases force and the permitted speed while using fuel more quickly. The current rules use 1.6 times the force, 1.25 times the speed limit and twice the fuel consumption; this is not a promise of the same acceleration on every slope.

“Live vehicle gauges accompany temporary boost, its sound and increased fuel consumption.”

The clips show a brief controlled boost followed by braking and a dashboard inspection. The early movement is kept separate from the stopped readings, and the footage is not a sustained-speed or frame-rate benchmark.