feat(12-factor-app): add configurations to deploy as 12 factor app [WD-11371]

[lorumic]

Done

• Added configuration files (rockcraft.yaml, charmcraft.yaml) and deploy.yaml workflow to deploy the website as a 12-factor application.

Issue / Card

Fixes WD-11371

[webteam-app]

Demo

Jenkins

demos.haus

[lorumic]

Can we reference the charm/lib/charms directory as a library in a remote repository? Otherwise, we end up copying into each website and maintaining becomes very hard.

I think we should probably exclude the lib folder and its content from version control. These are libraries that are fetched when running the charmcraft fetch-libs command, so we can consider them as "build artifacts" in a sense.

Regarding the remote repository idea, I don't think that can work, because each website can have different dependencies.