- Fix Entity3D self-reference cycle: replace raw `self` pointer with
`pyobject` strong-ref pattern matching UIEntity (closes#266)
- TileLayer inherits Grid texture when none set, in all three attachment
paths: constructor, add_layer(), and .grid property (closes#254)
- Add SpatialHash::queryCell() for O(1) entity-at-cell lookup; fix
missing spatial_hash.insert() in Entity.__init__ grid= kwarg path;
use queryCell in GridPoint.entities (closes#253)
- Add FOV dirty flag and parameter cache to skip redundant computeFOV
calls when map unchanged and params match (closes#292)
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
