Haste v1.1.4 V39 — Distant Horizons water compile fix

Fix
- Declared `distanceToCamera` at the start of `dh_water.fsh` using the DH water fragment's view-space position. This fixes the GLSL C1503 undefined-variable compilation error in V38.
- Kept the V38 depth-occlusion and LOD-smoothing changes otherwise unchanged.

Testing note
- Archive integrity and source-level checks are validated. A live Minecraft/Iris/Distant Horizons render is still required to confirm visual behavior.
