Cap maximum vehicle bash vs terrain

[RenechCDDA]

Summary

Balance "Cap maximum vehicle bash vs terrain (to prevent bashing thru concrete etc)"

Purpose of change

I have been told that someone drove a forklift straight through concrete walls. What.

Describe the solution

There is no vehicle depicted ingame that can reasonably survive a collision with a concrete wall of any type. So cap the maximum bash damage so this doesn't happen.

I also upgraded the bash damage from #82498 to a constant at the same time, rather than leaving it as a "magic number". (it also got reduced by 10, from 79--->69. Because I was wrongly looking at the reinforced concrete walls before.)

Describe alternatives you've considered

Also, make sure that it always just kills the player at higher speed?

Testing

Haven't even compiled. But does need testing.

Additional context