Bulletproof type coercion + full traceback logging in chat_fn

Ignore Gradio session history + bake identity facts into system prompt

Revert gradio 5.x bump (HF Dockerfile forces 4.44); pin starlette+fastapi instead

Simplify: drop multi-tab Blocks wrapper (broken queue init in Gradio 4.x)

Fix: ChatInterface in Gradio 4.x doesn't accept api_name kwarg

Bootstrap: app.py

initial commit