fix: Expunge notification objects from the session and add robust JSO…

[pwei1018]

Fix error:

File "/code/.venv/lib/python3.12/site-packages/flask/app.py", line 917, in full_dispatch_request
rv = self.dispatch_request()
^^^^^^^^^^^^^^^^^^^^^^^
File "/code/.venv/lib/python3.12/site-packages/flask/app.py", line 902, in dispatch_request
return self.ensure_sync(self.view_functions[rule.endpoint])(**view_args) # type: ignore[no-any-return]
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/code/.venv/lib/python3.12/site-packages/flask_jwt_oidc/jwt_manager.py", line 273, in decorated
return f(*args, **kwargs)
^^^^^^^^^^^^^^^^^^
File "/code/.venv/lib/python3.12/site-packages/flask_jwt_oidc/jwt_manager.py", line 226, in wrapper
return f(*args, **kwargs)
^^^^^^^^^^^^^^^^^^
File "/code/.venv/lib/python3.12/site-packages/flask_pydantic/core.py", line 285, in wrapper
res = func(*args, **kwargs)
^^^^^^^^^^^^^^^^^^^^^
File "/code/src/notify_api/resources/v1/notify.py", line 38, in send_notification
return jsonify(notification.json), HTTPStatus.OK
^^^^^^^^^^^^^^^^^
File "/code/src/notify_api/models/notification.py", line 118, in json
"id": self.id,
^^^^^^^
File "/code/.venv/lib/python3.12/site-packages/sqlalchemy/orm/attributes.py", line 569, in get
return self.impl.get(state, dict_) # type: ignore[no-any-return]
^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/code/.venv/lib/python3.12/site-packages/sqlalchemy/orm/attributes.py", line 1096, in get
value = self._fire_loader_callables(state, key, passive)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/code/.venv/lib/python3.12/site-packages/sqlalchemy/orm/attributes.py", line 1126, in _fire_loader_callables
return state._load_expired(state, passive)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/code/.venv/lib/python3.12/site-packages/sqlalchemy/orm/state.py", line 803, in _load_expired
self.manager.expired_attribute_loader(self, toload, passive)
File "/code/.venv/lib/python3.12/site-packages/sqlalchemy/orm/loading.py", line 1682, in load_scalar_attributes
raise orm_exc.ObjectDeletedError(state)
sqlalchemy.orm.exc.ObjectDeletedError: Instance '<Notification at 0x7f8e6c2c39e0>' has been deleted, or its row is otherwise not present.
}