* appdata: use appstreamcli for appdata validation
appstream-util is obsoleted by appstreamcli.
* appdata: Update appdata
- Add translation tag
- Add categories and keywords tags
* Capitalize keywords to avoid duplicate strings
* Remove catrgories and keywords
They are unnecessary for Flathub
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Co-authored-by: kramo <contact@kramo.hu>
e5f8e81c2e
