fix: bump gradio to 5.0.0 (build was stuck on 4.40.0)

fix: drop CUDA wheel index (CPU-basic build) - use default llama-cpp-python wheel

v2: clinical decision support repositioning + multi-turn chat + 5 PT-BR examples + canonical lookup

init: araras-gemma4 demo (Gradio + ZeroGPU)

initial commit