Provide default configuration for celesita-app and celestia-node for projects that aren't concerned with how they are configured

[chatton]

When working with tastora across different repos, there ends up being a lot of boiler plate with setting up of celestia-app and celestia-node that is duplicated across projects.

While this makes sense for writing tests within the celestia-app and celestia-node repos, when everything needs to be fully customizable, when we want to write a test from ev-node or ev-abci, in most cases we will want just one configuration that has everything as standard settings as we essentially just want a DA host address to point at.

This can be achieved by exposing a default builder for celestia-app / celestia-node for use in other projects.