feat: add deterministic goat routine

tests/simulation_state_serialization_test.gd

@@ -20,6 +20,7 @@ func _run() -> void:
 	_test_previous_world_retention_migration()
 	_test_previous_world_opportunity_migration()
 	_test_previous_world_animal_migration()
+	_test_previous_world_routine_migration()
 	_test_relationship_schema_rejection()
 	_test_opportunity_schema_rejection()
 	_test_animal_schema_rejection()
@@ -498,6 +499,41 @@ func _test_previous_world_animal_migration() -> void:
 	manager.free()
 
 
+func _test_previous_world_routine_migration() -> void:
+	var manager := _create_manager(65)
+	var v10_data: Dictionary = manager.create_state_record().to_dictionary()
+	v10_data["schema_version"] = SimulationStateRecord.ROUTINE_LEGACY_SCHEMA_VERSION
+	v10_data["animals"] = [
+		{
+			"schema_version": AnimalStateRecord.LEGACY_SCHEMA_VERSION,
+			"animal_id": "legacy_goat",
+			"display_name": "Legacy",
+			"species_id": String(SimulationIds.SPECIES_GOAT),
+			"position": [-4.0, 0.0, -11.5],
+			"hunger": 40.0,
+			"last_fed_tick": AnimalStateRecord.NEVER_FED_TICK,
+			"reserved_by": -1,
+			"enabled": true,
+			"can_npcs_feed": true,
+			"can_player_feed": true,
+		}
+	]
+	var migrated := SimulationStateRecord.from_dictionary(v10_data)
+	_check(migrated != null, "World schema v10 should preserve and upgrade animal records")
+	if migrated != null:
+		var animal := migrated.animals[0]
+		_check(
+			(
+				animal.get_animal_id() == &"legacy_goat"
+				and animal.get_routine_site_id().is_empty()
+				and not animal.has_active_travel_target()
+				and animal.get_next_routine_tick() == 0
+			),
+			"World v10 migration should add deterministic idle routine defaults"
+		)
+	manager.free()
+
+
 func _test_animal_schema_rejection() -> void:
 	var manager := _create_manager(64)
 	var missing_animals: Dictionary = manager.create_state_record().to_dictionary()
@@ -521,6 +557,11 @@ func _test_animal_schema_rejection() -> void:
 				"enabled": true,
 				"can_npcs_feed": true,
 				"can_player_feed": true,
+				"routine_site_id": "",
+				"travel_target_site_id": "",
+				"travel_target_position": [0.0, 0.0, 0.0],
+				"has_travel_target": false,
+				"next_routine_tick": 0,
 			}
 		)
 	)