tile_renderer: only render z=0 tiles on FloorTiles layer (D-049 z-stack). entity_renderer: fix footprint from 24x24 to 24x32 per D-044, split ENTITY_SIZE into ENTITY_WIDTH/ENTITY_HEIGHT with separate offsets. game_state: add follow_target_id stub for server ticket #241. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>