Move Py_FinalizeEx call to end of isolate function

Removed AppLifecycleListener-based finalization and now explicitly call cpython.Py_FinalizeEx() at the end of runPythonProgramInIsolate. This ensures Python finalization occurs after the program finishes, improving resource management.

Author: FeodorFitsner

src/serious_python_android/lib/src/cpython.dart

@@ -96,16 +96,6 @@ Future<String> runPythonProgramInIsolate(List<Object> arguments) async {
     _debug("after Py_Initialize()");
   }
 
-  AppLifecycleListener(onDetach: () {
-    _debug("AppLifecycleListener: onDetach");
-    _withGIL(cpython, () {
-      if (cpython.Py_IsInitialized() != 0) {
-        cpython.Py_FinalizeEx();
-        _debug("after Py_FinalizeEx()");
-      }
-    });
-  });
-
   final result = _withGIL(cpython, () {
     final logcatSetupError = _setupLogcatForwarding(cpython);
     if (logcatSetupError != null) {
@@ -140,6 +130,9 @@ Future<String> runPythonProgramInIsolate(List<Object> arguments) async {
 
   _debug("Python program finished");
 
+  cpython.Py_FinalizeEx();
+  _debug("after Py_FinalizeEx()");
+
   sendPort.send(result);
 
   return result;