BrainForge/Security: direct vLLM (4090), HANA persona cache, Security stub

Simplify conversation ending: two clean closing messages after winding_down

Strip thinking content from all LLM responses and skip redundant role generation

Add AI-completed vs exact role generation style toggle

Improve freeform role generation prompt and expose finish_reason

Add response timing, chat stats, and role prompt viewer to settings

Rebrand UI with Neon.ai header, sidebar styling, expert personas, and UX improvements

Add Neon HANA routing, per-request timeouts, and chat brevity prompts

Add freeform persona input mode with file upload and Developer menu toggle

Initial commit: LLMChats3 - LLM conversation app with React + FastAPI, persona config, orchestrated conversation lifecycle, collapsible sidebar accordions, stop button, and export capabilities