Add github action for publishing releases

[strazto]

No description provided.

[strazto]

This should work as-is, although you may need to initalize an orphan branch, manifest-release for it to run the first time.

From now on, the workflow for releasing just involves publishing a release from a tag.

The generated manifest.json won't include any of the previous releases unless they're tagged & released on github.

Every commit to main also triggers a workflow that pushes build assets to a "nightly" release.

This release will always have a version of 0.0.0.9000

If you'd rather the repo file that you give to users not contain nightlies, you can change the "pagesBranch" parameter of the action to something else.

    - name: Publish Plugin Manifest
      uses: matthewstrasiotto/jellyfin-plugin-repo-action@dev-working
      with:
        ignorePrereleases: false
        githubToken: ${{ secrets.GITHUB_TOKEN }}
        repository: ${{ github.repository }}
        pagesBranch: manifest-release
        pagesFile: manifest.json

Change pages-branch or pages-file to something that distinguishes the nightlies repo

[9p4]

Why always 0.0.0.9000?

[strazto]

I chose it so that end users wouldn't pick it

[9p4]

I merged this, and as I did, I had a lot of questions pop up in my head.

First of all, why aren't we using https://github.com/Kevinjil/jellyfin-plugin-repo-action over your fork?

Second, can we trust these actions with a token? I'd prefer to avoid supply chain attacks.

[9p4]

Feel free to create another PR so we can continue the discussion there.