Added Streamer Icon to Notifications

[ghost]

Tested on Gnome 42.

Before:

After:

[ghost]

Added "Show streamer icon on notifications" to the settings panel.

[ghost]

By default, the "Show streamer icon on notifications" setting is disabled, so I've made livestreamer-icons/twitchlive.svg the default icon.

Disabled:

Enabled:

[maweki]

First of all, thank you for your contribution. Looks good to me. As a heads up: I will squash all those commits and the next release (and all future ones) will be targeting gnome 43 only/and later. So I won't do a release with this feature for 42 or earlier. Hope that's fine.

[ghost]

That's fine. Thank you for a perfect extension! :smile:

[maweki]

Really cool would be if the new option was disabled if neither of the notification options are enabled.

[ghost]

Demo.webm

[maweki]

Oh no, you should never change the flow of the UI. The elements should be disabled (greyed out) so that they are unusable if they have no effect.

Sorry for the miscommunication.

[ghost]

Demo.webm

[maweki]

I think that looks quite good. Just give me a heads up that you're also done and happy and I'll do the merge.

[ghost]

I'm ready for the changes to be merged.