Remove About tab, replace exposed API key with generic message

Upload complete V3.1 app.py with all 12 tabs

V3.1: Synthetic data fallback + removed hardcoded K2 key from docs

V3.0: Add rate-limit resilience (cache+retry) for HF Spaces

V3.0: Bloomberg terminal UI, 10 quant modules, Jane Street feature docs

Restore app.py + fix share=True for HF Spaces

Fix share=False to share=True for HF Spaces