Chore: Upgrade runners to Ubuntu 26.04 (#14347)

* Moves runners to 26.04 and a few jobs to -slim variant

* Probably fixing the imagemagik 7 problems and maybe the frontend playwright thing?

* Compare thumbnails, but allow a little difference in the perceptual hash

.github/workflows/translate-strings.yml

@@ -8,7 +8,7 @@ env:
 jobs:
   generate-translate-strings:
     name: Generate Translation Strings
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-26.04
     environment: translation-sync
     permissions:
       contents: write