PoC Flatpak packaging

[tinywrkb]

Here's an initial Flatpak packaging manifest for GTKTerm.
The package can easily be built with Flatpak Builder.

I quickly tested the app with USB to TTL, and as far as I can tell, it's working as expected.

The following should be handled before considering publishing via Flathub.org:

• The config file should be in XDG_CONFIG_HOME. HOME is the worst location for a config file because it mandates the use of the --persist=. permission, which is a bit buggy.
• AppStream appdata/metainfo is missing.

Optional changes:

• Use reverse DNS naming scheme for the installed desktop file and icon file names. e.g. com.github.Jeija.GTKTerm.desktop.
• Evaluate and use the Device Portal to avoid the permissive --device=all permission.

[Jeija]

Hi @tinywrkb 👋 !

I'm certainly open to adding / improving Flatpak support and am happy for any help in that regard. Concerning the issue with the configuration file location, see my comment in #40.
Since I am not too familiar with how Flatpak handles permissions: With my suggested behavior, gtkterm checks if .gtktermrc exists in $HOME before potentially creating one in $XDG_CONFIG_HOME. I am wondering if checking for existence of the configuration file in $HOME will cause any issues with Flatpak support?

[tinywrkb]

@Jeija thanks for solving the config file location issue.

I am wondering if checking for existence of the configuration file in $HOME will cause any issues with Flatpak support?

No, I don't see a reason why it will.

I tested fe66238 and it works as expected.

[Jeija]

Thanks for taking the time to test fe66238! I have now merged it into the master branch.