Textures: Linear/Nearest labels; prove the filter pass does not resample pixel art (#68)

Dropdown labels are now Linear (default) and Nearest; the stored values
linear/nearest are unchanged, old project files load as before.

e2e 12c-ii measures in Play at camera zoom 1.37 (screen scale 1.434): a
Nearest edge sampled across seven pixels is byte-identical with and without
a neutral Adjust colors shader, and brightness 0.5 on the same path darkens,
so the pass really runs there. New hook __gm.gameRect(id).

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

src/core/properties/PropertySchema.ts

@@ -138,8 +138,8 @@ const ASSET_SCHEMAS: Record<AssetType, PropertySchema> = {
       kind: 'enum',
       default: 'linear',
       options: [
-        { value: 'linear', label: 'Smooth' },
-        { value: 'nearest', label: 'Pixel art' },
+        { value: 'linear', label: 'Linear' },
+        { value: 'nearest', label: 'Nearest' },
       ],
     },
   ],