[25.06] sddm screen distorted on google-kukui/krane w/ plasma-desktop/systemd
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### Describe your issue
#### What's the expected behaviour?
sddm works out of the box
#### What's the current behaviour?
login-screen is not rendered correctly, graphical login not possible
#### How to reproduce your issue?
install the below stated image to a USB memory and boot the device from USB
### What device are you using?
google-kukui / google-krane
### On what postmarketOS version did you encounter the issue?
<!--
Replace space inside `[ ]` with `x` to fill the checkbox
-->
* [ ] edge (`master` branch)
* [x] `v25.06`
* [ ] `v24.12`
* [x] I confirm that the issue still is present after running `sudo apk upgrade -a`
### On what environment did you encounter the issue?
#### Environments
* [ ] COSMIC
* [ ] GNOME Shell on Mobile
* [ ] Phosh
* [ ] Plasma Mobile
* [ ] Sxmo (Wayland/Sway) **Please post the output of `sxmo_version.sh`**
* [X] Other: plasma-desktop
### Which init system are you using?
* [ ] OpenRC
* [X] systemd
### How did you get postmarketOS image?
* [x] from https://images.postmarketos.org/bpo/
* [ ] I built it using pmbootstrap
* [ ] It was preinstalled on my device
### What's the build date of the image? (in yyyy-mm-dd format)
20250610-0231-postmarketOS-v25.06-plasma-desktop-3-google-kukui.img.xz
### Additional information
very likely related to #3692
issue