Add to manifest when deploying a golem shiny app on connect

[novica]

This is more a feature idea that I don't know if it is possible.

If I understand things correctly, when I want to deploy a Shiny app that is written with Golem, from GitHub on Posit connect, the manifest file has to have the app as part of packages that need to be installed. This requires to install the app in the local environment with remotes::install_github() and then to rsconnect::writeManifest(). However, updating the manifest without having the app in the environment, removes the app from the manifest, and then the deployment is non-functional.

It seems like a good idea to have the option to say something like rsconnect::addToManifest() and then list the GitHub dependency, instead of having to remember to have it in the environment each time the manifest is rewritten.