feat: regrow finite berry sources toward their authored cap

tests/action_system_boundaries_test.gd

@@ -166,6 +166,8 @@ func _test_target_resolution_and_travel_are_separate() -> void:
 			"resource_id": String(SimulationIds.RESOURCE_FOOD),
 			"amount_remaining": 5.0,
 			"yield_per_action": 1.0,
+			"max_amount": 5.0,
+			"regrow_rate": 0.0,
 			"reserved_by": -1,
 			"enabled": true,
 			"can_npcs_use": true,
@@ -184,6 +186,8 @@ func _test_target_resolution_and_travel_are_separate() -> void:
 			"resource_id": String(SimulationIds.RESOURCE_FOOD),
 			"amount_remaining": 5.0,
 			"yield_per_action": 1.0,
+			"max_amount": 5.0,
+			"regrow_rate": 0.0,
 			"reserved_by": -1,
 			"enabled": true,
 			"can_npcs_use": true,

tests/food_storage_loop_test.gd

@@ -25,6 +25,8 @@ func _run() -> void:
 			"resource_id": String(SimulationIds.RESOURCE_FOOD),
 			"amount_remaining": 10.0,
 			"yield_per_action": 2.0,
+			"max_amount": 10.0,
+			"regrow_rate": 0.0,
 			"reserved_by": -1,
 			"enabled": true,
 			"can_npcs_use": true,

tests/resource_regrowth_test.gd

@@ -0,0 +1,132 @@
+extends SceneTree
+
+var failures: Array[String] = []
+
+
+func _initialize() -> void:
+	call_deferred("_run")
+
+
+func _run() -> void:
+	var manager := _create_manager(961)
+	var bush := ResourceNode.new()
+	bush.name = "RegrowBush"
+	bush.node_id = &"regrow_bush"
+	bush.action_id = SimulationIds.ACTION_GATHER_FOOD
+	bush.resource_id = SimulationIds.RESOURCE_FOOD
+	bush.initial_amount = 2.0
+	bush.max_amount = 5.0
+	bush.regrow_rate = 0.1
+	bush.debug_label_enabled = false
+	var interaction_point := Marker3D.new()
+	interaction_point.name = "InteractionPoint"
+	interaction_point.position = Vector3.ZERO
+	bush.add_child(interaction_point)
+	root.add_child(bush)
+	await process_frame
+	_check(
+		manager.register_resource_node(bush), "Regrowth test should bind a real finite ResourceNode"
+	)
+	var state: ResourceStateRecord = manager.get_resource_state(bush.node_id)
+	_check(
+		(
+			is_equal_approx(state.get_amount_remaining(), 2.0)
+			and is_equal_approx(state.get_max_amount(), 5.0)
+			and is_equal_approx(state.get_regrow_rate(), 0.1)
+		),
+		"Regrowth metadata should bind from the authored node"
+	)
+
+	_check(
+		is_equal_approx(manager.harvest_resource_node(bush), 2.0),
+		"Harvesting should deplete the regrowing bush into carried inventory"
+	)
+	_check(
+		is_equal_approx(state.get_amount_remaining(), 0.0),
+		"The regrowing bush should reach zero after harvesting"
+	)
+	manager.simulate_tick()
+	manager.simulate_tick()
+	_check(
+		is_equal_approx(state.get_amount_remaining(), 0.2),
+		"Regrowing resources should recover exactly their rate per simulation tick"
+	)
+	for _tick in 50:
+		manager.simulate_tick()
+	_check(
+		(
+			is_equal_approx(state.get_amount_remaining(), 5.0)
+			and state.get_amount_remaining() <= state.get_max_amount()
+		),
+		"Regrowth should stop at the authored maximum without creating extra food"
+	)
+
+	manager.simulate_tick()
+	var saved_json: String = manager.serialize_state()
+	var restored := _create_manager(962)
+	_check(
+		restored.restore_state_from_json(saved_json),
+		"Regrowing resource state should survive save and restore"
+	)
+	_check(
+		(
+			restored.get_state_checksum() == manager.get_state_checksum()
+			and is_equal_approx(
+				restored.get_resource_state(bush.node_id).get_amount_remaining(), 5.0
+			)
+			and is_equal_approx(restored.get_resource_state(bush.node_id).get_regrow_rate(), 0.1)
+		),
+		"Restore should preserve the regrow amount, cap, and checksum"
+	)
+	restored.free()
+
+	var v3_data: Dictionary = state.to_dictionary()
+	v3_data["schema_version"] = ResourceStateRecord.REGROW_LEGACY_SCHEMA_VERSION
+	v3_data.erase("max_amount")
+	v3_data.erase("regrow_rate")
+	var migrated := ResourceStateRecord.from_dictionary(v3_data)
+	_check(
+		(
+			migrated != null
+			and is_equal_approx(migrated.get_max_amount(), 5.0)
+			and is_equal_approx(migrated.get_regrow_rate(), 0.0)
+		),
+		"Resource v3 should migrate with its current amount as cap and no regrowth"
+	)
+
+	bush.queue_free()
+	manager.free()
+	_finish()
+
+
+func _create_manager(seed_value: int = 961) -> Node:
+	var manager: Node = load("res://simulation/SimulationManager.gd").new()
+	manager.simulation_seed = seed_value
+	manager.debug_logs = false
+	var home_positions: Array[Vector3] = [
+		Vector3(0.0, 0.0, 0.0),
+		Vector3(2.0, 0.0, 0.0),
+		Vector3(10.0, 0.0, 0.0),
+		Vector3(12.0, 0.0, 0.0),
+		Vector3(30.0, 0.0, 30.0),
+		Vector3(40.0, 0.0, 40.0),
+	]
+	manager.home_positions = home_positions
+	root.add_child(manager)
+	manager.set_process(false)
+	return manager
+
+
+func _finish() -> void:
+	if failures.is_empty():
+		print("[TEST] Resource regrowth passed: bounded recovery -> cap -> restore")
+		quit(0)
+		return
+	for failure in failures:
+		push_error("[TEST] " + failure)
+	quit(1)
+
+
+func _check(condition: bool, message: String) -> void:
+	if not condition:
+		failures.append(message)

tests/resource_regrowth_test.gd.uid

@@ -0,0 +1 @@
+uid://bxxet5dkxrk1p