Add update-widget plugin

[Astinator]

Adds update-widget a plugin to allow you to view the number of available updates from the bar and see updated versions from the panel. Has optional flatpak update checking support.

[kevichi7]

would also be cool to add noctalia-shell specific updates here I guess (such as plugins or noctalia-qs). As a toggle though

[Astinator]

Not quite sure how you would check for plugin updates but that sounds like a nice idea. Thanks!

[spiros132]

Some minor feedback about the PR :)

[spiros132]

Thank you for the PR, it looks great! :)

@ItsLemmy

[ItsLemmy]

LGTM, my only concerns are :

• this only works on Arch based distros and the plugin's title and readme should reflect that. "widget" is pretty generic term, so maybe call it "Arch updater" or something closer to it's actual functionality.
• the squatting of the launcher provider keyword "refresh" which is also way too generic , >arch-update would be better. We have a PR coming in soon in the shell that allows custom aliases of commands so people will be able to do aliases easily, ex: >paru => >arch-update

[Astinator]

Thanks for the feedback! I'll make changes to address those concerns.