fix(@projects/@magic-civilization): 🐛 fix empty culture tree rendering

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

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

@@ -81,6 +81,11 @@ func _ready() -> void:
 		await get_tree().create_timer(1.5).timeout
 	elif _scene == "culture_tree_proof":
 		await get_tree().create_timer(0.5).timeout
+		# DataLoader.load_theme must run before the proof scene constructs
+		# its CultureWeb — without it `get_all_culture()` is empty and the
+		# tree renders blank.
+		if DataLoader.get_all_culture().is_empty():
+			DataLoader.load_theme("age-of-dwarves")
 		get_tree().change_scene_to_file(
 			"res://engine/scenes/tests/culture_tree_proof.tscn"
 		)

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

@@ -25,6 +25,12 @@ func _ready() -> void:
 	if not env_name.is_empty():
 		_screenshot_name = env_name
 
+	# Ensure DataLoader is populated before TurnManager.get_culture_web()
+	# tries to build from `get_all_culture()`. Idempotent — every other
+	# proof scene calls this for the same reason.
+	if DataLoader.get_all_culture().is_empty():
+		DataLoader.load_theme("age-of-dwarves")
+
 	await get_tree().process_frame
 	_setup_game_state()
 	_show_culture_tree()