🔒 [security fix] Restrict overly permissive CORS policy

[bg-l2norm]

🎯 What: The overly permissive CORS policy (wildcard *) has been restricted to specific, trusted local domains.
⚠️ Risk: A wildcard CORS policy allows any website to make requests to the backend API and connect to the real-time SocketIO dashboard on behalf of a user, potentially leading to unauthorized data access or interaction.
🛡️ Solution: Updated app.py to explicitly allow only http://127.0.0.1:5000 and http://localhost:5000 for both Flask-CORS and Flask-SocketIO.

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PR created automatically by Jules for task 9214360665732583099 started by @bg-l2norm

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