Ticket #563. Light fog alpha tuned to 0.25-0.35 range (was 0.25-0.55),
deep fog alpha set to 0.55-0.70 with zone temperature tint from
zone_tint_tex (bar=warm #2a1f15, hub=cool #1a1f2e, corridor=neutral
#1a1a1a). Two Perlin noise cycles: 8-10s light, 15-20s deep.
Zone tint texture now populated per-tile from server zone_id in
fog_state.gd with preservation across texture resizes.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Reduce from 5-layer to 3-layer fog: clear (forward cone), explored
(light overlay preserving art), and unexplored (solid near-black).
Remove peripheral sector handling from fog_state.gd.
Also preserve exploration data across texture resizes — previously,
resizing the fog texture lost all explored-tile state, causing tiles
behind the player to render as unexplored black instead of light fog.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Define VIS_HIDDEN/PERIPHERAL/FORWARD and EXP_UNEXPLORED/EXPLORED/
VISIBLE in FogState. Replaces 7 magic number usages in _resize() and
update_from_state(). Provides stable assertion targets for fog tests.
Implements #476.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>