alejandrolucas08-better/Symphonia ? reverse-engineered prompt

Build me a web app called Symphonia for two people who speak different languages to have a real time audio call together.

I want a polished frontend with routes for login, register, home, call setup, and the call screen, with a simple demo flow that works even before the backend is fully connected. The call UI should show the participants, live transcription, translated messages, chat, call controls, and a clear visual audio signal. Make it feel mobile friendly and support reduced motion too.

Also set up the backend for authentication, call handling, and an authenticated WebSocket for live call events, with best effort PCM audio relay between two participants. Use PostgreSQL for storage and make it easy to run everything locally with Docker Compose.

If anything is unclear, check the existing docs and look up current docs online if you need to. I mainly want a working MVP that feels complete and is ready for iterative improvements.