[Blocker] fix: v2.3 — Pure kinematic, hapus raycast, Y di-clamp ke track surface

## GitHub Update **Repository:** [MKWcorp/carrstret](https://github.com/MKWcorp/carrstret) **Author:** Carrstret Dev **Date:** 3/27/2026, 3:17:50 PM **Commit:** [`7987b7f`](https://github.com/MKWcorp/carrstret/commit/7987b7f46d0949f798bd24bb3a8c585976caa6e4) ### Commit Message fix: v2.3 — Pure kinematic, hapus raycast, Y di-clamp ke track surface PENDEKATAN BARU: Tidak ada raycast, tidak ada gravity, tidak ada velY. Mobil Y selalu = TRACK_Y + CAR_SEAT_H = 0.65 (hardcoded). 100% reliable — tidak bisa terbang, tidak bisa tembus track. Arcade feel tetap ada karena movement XZ tetap physics-based. --- _This story was imported from historical commits._