refactor: enhance test framework with automated resource tracking and scripted error capture capabilities

tests/helpers/gridmap_mock.gd

@@ -0,0 +1,24 @@
+extends Node
+
+# Minimal EnhancedGridMap stand-in for Gauntlet headless tests. Records
+# set_cell_item calls so lifecycle tests can run the local sync path without a
+# real GridMap. Only the surface the manager touches is implemented.
+
+var cell_size := Vector3(1, 1, 1)
+var cells: Dictionary = {} # Vector3i -> item id
+var astar_inits := 0
+
+func set_cell_item(pos: Vector3i, item: int, _orientation: int = 0) -> void:
+	if item == -1:
+		cells.erase(pos)
+	else:
+		cells[pos] = item
+
+func get_cell_item(pos: Vector3i) -> int:
+	return cells.get(pos, -1)
+
+func initialize_astar() -> void:
+	astar_inits += 1
+
+func update_grid_data() -> void:
+	pass