CI: Update first-party GitHub Actions

CI: Update Python version to 3.13

CI: Update marian-code/python-lint-annotate

checks: Check for game captures needing admin

plugins: List not loaded plugins

plugins: List disabled plugins

linux: Cleanup some inconsistencies in help texts

linux: Raise `LEVEL` for "undefined" conditions

linux: Detect unofficial Flatpaks

linux: Check for no desktop portal being present

simplehttp: Simplify simplehttp, updating to newer python standards

obsversion: Fix pep8 formatting error

checks: Properly handle lack of OBS version

checks: Use bespoke version parser

utils: Add bespoke version parser