feat: bake jajce terrain navigation

tests/jajce_runtime_integration_test.gd

@@ -11,7 +11,8 @@ func _run() -> void:
 	var main_scene: Node = load("res://main.tscn").instantiate()
 	root.add_child(main_scene)
 	await process_frame
-	await physics_frame
+	for _frame in 10:
+		await physics_frame
 
 	var simulation_manager: Node = main_scene.get_node("SimulationManager")
 	simulation_manager.set_process(false)
@@ -27,10 +28,9 @@ func _run() -> void:
 		"Runtime Terrain3D should bind to the gameplay camera"
 	)
 	_check(terrain.collision_mode != 0, "Runtime Terrain3D collision should be enabled")
-	var greybox_ground := main_scene.get_node("JajceWorld/NavigationRegion3D/GreyboxGround") as StaticBody3D
 	_check(
-		greybox_ground.collision_layer == 0 and greybox_ground.collision_mask == 0,
-		"Runtime GreyboxGround should not provide physics collision"
+		not main_scene.has_node("JajceWorld/NavigationRegion3D/GreyboxGround"),
+		"Runtime should not keep the temporary greybox navigation ground"
 	)
 	_check(
 		(
@@ -49,6 +49,11 @@ func _run() -> void:
 	)
 
 	var navigation_map: RID = main_scene.get_world_3d().navigation_map
+	var navigation_region := main_scene.get_node("JajceWorld/NavigationRegion3D") as NavigationRegion3D
+	_check(
+		navigation_region.navigation_mesh.resource_path == "res://world/jajce/JajceNavigationMesh.tres",
+		"Runtime navigation should use the Terrain3D-derived baked mesh resource"
+	)
 	await _wait_for_navigation_map(navigation_map)
 	NavigationServer3D.map_force_update(navigation_map)
 
@@ -82,6 +87,9 @@ func _run() -> void:
 			_check_path_tracks_terrain(
 				terrain, path, "Runtime navigation path should track Terrain3D height"
 			)
+			_check_path_reaches_destination(
+				path, destination, "Runtime navigation path should reach its requested target"
+			)
 
 	var village := SimVillage.new()
 	var worker := SimNPC.new(100, "BaselineWorker", SimulationIds.PROFESSION_SCHOLAR, 5.0, 5.0)
@@ -152,3 +160,17 @@ func _check_path_tracks_terrain(terrain: Terrain3D, path: PackedVector3Array, me
 				% [message, point, terrain_height]
 			)
 			return
+
+
+func _check_path_reaches_destination(path: PackedVector3Array, destination: Vector3, message: String) -> void:
+	if path.is_empty():
+		return
+
+	var final_point := path[path.size() - 1]
+	var final_xz := Vector2(final_point.x, final_point.z)
+	var destination_xz := Vector2(destination.x, destination.z)
+	if final_xz.distance_to(destination_xz) > 1.5:
+		failures.append(
+			"%s: final path point %s is too far from %s"
+			% [message, final_point, destination]
+		)