feat: simulation speed control with bracket keys

Press [ to slow down, ] to speed up through 6 levels: 0.25x, 0.5x, 1x, 2x, 4x, 10x. Clock delta is multiplied by the current speed, so time_of_day advances proportionally and the visual day-night cycle stays synced. Current speed shown in the village panel header. 10x makes a full day cycle watchable in ~24 seconds. Speed changes are non-destructive to simulation determinism.

world/ui/ui.gd

@@ -27,6 +27,8 @@ func _ready() -> void:
 		push_error("VillageUI: SimulationManager has no npc_decision_recorded signal")
 	if simulation_manager.has_signal("state_restored"):
 		simulation_manager.state_restored.connect(_on_state_restored)
+	if simulation_manager.has_signal("speed_changed"):
+		simulation_manager.speed_changed.connect(_on_speed_changed)
 
 	if "village" in simulation_manager:
 		_on_village_changed(simulation_manager.village)
@@ -63,9 +65,12 @@ func _on_village_changed(village: SimVillage) -> void:
 		event_text = ""
 	else:
 		event_text = "\n" + event_text
+	var speed_text := ""
+	if simulation_manager.has_method("get_current_speed"):
+		speed_text = simulation_manager.get_current_speed()
 	village_stats_label.text = (
 		"""
-	Village
+	Village   [%s]
 
 	Food: %s
 	Wood: %s
@@ -79,6 +84,7 @@ func _on_village_changed(village: SimVillage) -> void:
 	%s
 	"""
 		% [
+			speed_text,
 			round(village.food),
 			round(village.wood),
 			round(village.safety),
@@ -101,6 +107,11 @@ func _on_state_restored() -> void:
 	_refresh_npc_inspector()
 
 
+func _on_speed_changed(_multiplier: float) -> void:
+	if simulation_manager != null and "village" in simulation_manager:
+		_on_village_changed(simulation_manager.village)
+
+
 func _refresh_npc_inspector() -> void:
 	if not debug_overlay_visible:
 		return