Build and publish appimage

[mutlusun]

Hello,

based on the discussion in this MR in the quarto-cli repository, I propose here a merge request to add appimage builds for quarto.

Original description:

This PR adds an appimage build to the release tarballs. Appimage is a packaging format that runs on linux and is able to provide all necessary files within one file/package. Users only need to download the file, make it executable, and can run the software. This eliminates the manual moving of the tarball to /opt/ what requires root privileges and symlinking, etc. (see the tarball installation guide).

Related issues: quarto-dev/quarto-cli#4505

The current MR creates an appimage and uploads it as an artifact. However, the code to publish/distribute the appimage is still missing. I see the following ways to do this:

• Provide a link in the readme to the latest artifact. However, as I understand this discussion this is currently not possible as artifacts are only accessible to logged in users and only for 90 days. Do you know a workaround here?
• Upload the artifact as release tarball within Github. This is probably the easiest solution. The Github Actions bot creates for every quarto release a new commit. It would be necessary that this bot does not only create a commit but also a tag as it is not possible to upload a release tarball without a corresponding tag. Would you agree to this solution?
• Upload the artifact to another host/drive (comparable to what is done with the Chocolatey package). However, appimage does not have a central repository. Thus, it would be necessary to have some online space.

What do you think is the best approach to go forward? Thank you very much for your feedback!

Todo:

• Document appimage in readme.