feat: add demo video link to landing page

Upadted Readme

Optimize summary generation: parallel execution and increased timeout

Fix deployment summary error handling

Fix summary persistence and improve sign in button styling

Fix 504 timeout: Optimize Gemini AI summary generation with faster prompts, token limits, and timeout handling

Update backend build

Update Gemini AI model to gemini-2.5-flash and update API key

Merge remote changes and update Gemini model to 2.0-flash-exp

Update Gemini AI model from discontinued versions to gemini-2.0-flash-exp

Delete TRANSCRIPTION_TESTING_GUIDE.md

Delete GIT_CLEANUP_GUIDE.md

Update README.md

Update README.md

� feat: Enhanced multi-user transcription system