Automate PR to typst pkgs

[otytlandsvik]

⚠ depends on #43

The process of publishing this template to the typst universe is manual, cumbersome, and error prone currently. For a more robust publishing process we should automate creating a PR to typst pkgs. This will ensure published content does not regress from its source in this repository, and that the template is easier to maintain in the future.

This could be a part of the release action.

An additional enhancement would be to insert the generated changelog found in the github releases into the README of the template on typst pkgs.

[mrtz-j]

A possible solution via the tyler CLI.