fix(client): address PR #22 review — 3 critical bugs, 2 warnings, 8 suggestions

Critical fixes:
- fog_state: guard _compute_bounds() against all-invalid tiles (negative Rect2i crash)
- fog_shader: read Camera2D zoom dynamically instead of hardcoded Vector2(2,2)
- world_radial: set custom_minimum_size in _ready() from spoke geometry

Warnings:
- fog.gdshader: tighten PERIPHERAL_LOW 0.15→0.55 to match D-059 peripheral band
- Extract color_for_entity_kind() to Constants.gd, decouple CursorRenderer from EntityRenderer

Documentation: shallow copy assumption, gradual decay TODO, tween guard rationale,
fade timing rationale, ToggleInsert TODO, monologue consume-once, hover offset safety,
v6 fixture gap TODO.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

client/scripts/constants.gd

@@ -58,6 +58,15 @@ const ENTITY_COLOR_HOSTILE: Color = Color("#d45d5d")    # Hostile/Dangerous —
 const ENTITY_COLOR_OBJECT: Color = Color("#8b8ba0")    # Static objects — muted grey
 const ENTITY_COLOR_PLAYER: Color = Color("#e0e8ff")    # Player character (detective)
 
+# D-033 color lookup by entity kind (Phase 1: defaults, Phase 2 #361: relationship-based)
+static func color_for_entity_kind(entity_data: Dictionary) -> Color:
+	var kind_variant: String = entity_data.get("kind", {}).get("variant", "")
+	match kind_variant:
+		"Player": return ENTITY_COLOR_PLAYER
+		"Npc": return ENTITY_COLOR_UNKNOWN
+		"Object", "Terrain": return ENTITY_COLOR_OBJECT
+		_: return ENTITY_COLOR_OBJECT
+
 # D-015: Peripheral vision dimming
 const PERIPHERAL_ALPHA: float = 0.5