Cloverpit: canvas pointer lock so look doesn't stop at screen edge

[Galethis]

Problem

Pointer lock was working (cursor hides) but look still stopped at the screen edge.

That happens when lock is not on the Unity #unity-canvas itself — the browser/game still uses absolute mouse coords that clamp at the edge.

Fix

Surgical add to Games/cloverpit/index.html only:

• On first click / pointerdown, call requestPointerLock() on #unity-canvas
• Prefer { unadjustedMovement: true } (raw deltas) with normal fallback
• Re-lock on later clicks if lock was lost
• No button / overlay

Test

1. Merge & hard-refresh
2. Launch Cloverpit
3. Click the game once
4. Move mouse continuously in one direction — camera should keep turning with no edge stop

Esc still exits pointer lock (browser default).

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