Create .env file to define host and port for public internal requests

[talyguryn]

These host+port will be used to run backend and initialise frontend.

for example

local machine environment:

• http://localhost:3000 as backend
• http://localhost:3080 as sockets endpoint

prod environment:

• https://team.codex.so as backend
• wss://team.codex.so as sockets endpoint