Fix and modernize fallback theme
The fallback theme was using PlasmaComponents 2 and wasn't working at all in Plasma 6.
This commits ports it to modern components so that it works again, and gets rid of some unnecessary old code and old QML paradigms in the process.
BUG: 467056 FIXED-IN: 6.0
To test, break your lock screen theme and lock the screen. You should see the fallback theme now:
| Greeter | Session switcher |
|---|---|
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Edited by Nate Graham