Force handling errors globally:

Configured Flask and Flask-RESTful to propagate JWT exceptions correctly by adding the following code to init.py:

app.config['PROPAGATE_EXCEPTIONS'] = True  # Propagate exceptions to the client
api.handle_errors = False                  # Disable Flask-RESTful 

This provided the results I was looking for and I successfully tested the JWT lifecycle:

1. Login: Issued JWT tokens via /api/login.

2. Valid Token: Accessed protected resource successfully.

3. Expired Token: Received expected 401 error ("Token has expired").

4. Token Refresh: Successfully refreshed JWT token via /api/refresh.

5. New Token: Validated new token with protected endpoint access.