Update README.md

Rewrite README: full architecture, remove quest table, clear project description

Improve README: feature drug safety check, all 6 quests, clean architecture

Fix: pin gradio 6.11.0 — version that has gr.Server

Fix: use gradio 6.0.0 sdk_version - resolves HfFolder error

Fix: upgrade to gradio 5.x, drop conflicting pins

Fix Python 3.13 audioop error - pin py3.11 + add pyaudioop

Fix README color metadata

initial commit