feat(@projects/@magic-civilization): ✨ add theme asset setup for headless rendering

Co-Authored-By: Lilith Autocommit <noreply@atlilith.com>

src/game/engine/scenes/tests/iter_7q_worldmap_visual_proof.gd

@@ -47,6 +47,11 @@ func _setup_game() -> void:
 	print("iter_7q: Loading theme...")
 	DataLoader.load_theme("age-of-dwarves")
 	DataLoader.load_world("earth")
+	# Without ThemeAssets.set_theme the renderer's per-sprite ThemeAssets
+	# lookups all fail and the world_map paints black under headless
+	# llvmpipe. main.gd already calls this on app boot; proof scenes that
+	# bypass main.gd must do it themselves.
+	ThemeAssets.set_theme("age-of-dwarves")
 
 	var settings: Dictionary = {
 		"seed": 42,