* Add files for flathub compliance
Please see: https://github.com/flathub/flathub/pull/7783
This adds the requested files to the upstream git repo, and adds the
screenshot.png so it may be sourced from Stoat, rather than from a user
repository.
* chore: update product screenshot
* chore: update desktop entry comment
* chore: update icon
* chore: update summary to current github tag
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Co-authored-by: Shawn W Dunn <sfalken@opensuse.org>
Co-authored-by: izzy <me@insrt.uk>
