Handle ZeroGPU CUDA init failures with chat fallback

Add hybrid semantic retrieval with optional reranker

Relax keyword search for natural-language chat prompts

Harden metadata cache validation for sector/location coverage

Fix NEPATEC metadata parsing for list-valued fields and invalidate bad cache

Fix Gradio Dataframe args for v6.5.1

Harden startup, Gradio compatibility, and metadata loading paths

Fix ChatInterface arg for Gradio 6 and normalize history format

Fix Gradio Chatbot init for Space runtime

Update README.md

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