Add postgres adapter for socket.io

[rbren]

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To run this PR locally, use the following command:

docker run -it --rm   -p 3000:3000   -v /var/run/docker.sock:/var/run/docker.sock   --add-host host.docker.internal:host-gateway   -e SANDBOX_RUNTIME_CONTAINER_IMAGE=docker.all-hands.dev/all-hands-ai/runtime:dbda7bc-nikolaik   --name openhands-app-dbda7bc   docker.all-hands.dev/all-hands-ai/openhands:dbda7bc

[diwu-sf]

Hi, would you also be willing to add in the socket.io redis adapter?
Postgres NOTIFY / LISTEN doesn't really scale when PGBouncer / any kind connection pooling is used in between the app server and the postgres. Having all app servers direct connect to postgres is also an anti-pattern for scaling due to postgres' process-per-client architecture.

Redis would be a more usable pub-sub infra, and in our stack, we use Redis already with dramatiq for background async tasks

[rbren]

@diwu-sf we are switching to postgres!

[rbren]

err...we are switching to redis!

[diwu-sf]

Okay great, make a lot more sense for scaling.