Add Dictionary validation in game_state visible_tiles loop to prevent crash on malformed data (Hoshe critical). Skip redundant modulate.a writes (Hoshe suggestion). Add 3 tests: malformed visible_tiles, facing rotation accuracy, v1 backward compatibility. Clarify D-033 Phase 1/Phase 2 comments. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>