Fix #5168: Monster truck body lighting flickers when pushed

[iManGaaX]

Summary

Monster truck body lighting flickers between bright and dim when a player pushes the truck

ped-vs-wheel collisions write extreme lighting values (0x00 or 0xFF) to the per-wheel lighting bytes, which alternate with the ground value (0xBB) every frame - the visible flicker; the engine also resets the wheel bytes to a dim default (0x48) on respawn, so the body starts dark until the first ground collision

Fix: two hooks

1. CMonsterTruck::ProcessEntityCollision; skip writing 0x00 and 0xFF to the wheel lighting byte, so only real ground/surface lighting (0x40-0xE0) updates it

2. CVehicle::PreRender; clamp the final m_fLighting to a minimum of 0.36 (0xBB asphalt) for monster trucks, so the body is never darker than the ground it stands on, from the moment it spawns

Both hooks are scoped to monster trucks (444, 556, 557)

Closes #5168.

Before ->

2026-09-14.05-47-59.mp4

After ->

2026-09-14.05-44-01.mp4

Checklist

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