App should listen on incoming signals when running in a container

[smuu]

Summary

When running celestia-app in a container I expect that it handles signals without running in a container. E.g. CTRL + C (SIGINT) for terminating the application.

Problem Definition

Better developer experience and consistency with usage.

Running the command below you can't exit the container using CTRL + C (Sends the SIGINT signal).

docker run --sig-proxy=true -v ~/.celestia-app/config/genesis.json:/opt/config/genesis.json:ro ghcr.io/celestiaorg/celestia-app:0.12.0-rc6 start

Proposal

I never worked with signal handling in go. There may be some forwarding on signals needed, probably in the Dockerfile.