File Explorer (GNU/Linux): Keep synchronization status icons at a fixed size, regardless of thumbnail size

## Feature request

**Which Nextcloud Version are you currently using:** 31.0.10 with Desktop Sync Client 4.0.4 and Linux Mint Cinnamon 22.2 (not checked with Windows 11 or other GNU/Linux desktop environment).

**Is your feature request related to a problem? Please describe.**
Not so long ago (e.g. https://github.com/nextcloud/desktop/issues/5133), synchronization status icons were tiny. Since this was corrected, we now have the opposite problem. Two things are needed:
- The size of synchronization status icons should not be proportional to the size of preview thumbnails and should therefore have a fixed size (ideally configurable in the synchronization client settings, expressed in pixels).
- The default size should be smaller (scale ratio relative to that of preview thumbnails).

Below, the preview thumbnails are deliberately very large, and we can see that the synchronization status icons are enormous, which makes it difficult to see the previews clearly (It's very annoying when you're browsing through a folder with photos, for example). Regardless of size, this scale ratio is the same. These icons should be much smaller (but not as much as before (e.g. https://github.com/nextcloud/desktop/issues/5133), as mentioned above), and have a fixed size, completely independent of the size of the thumbnails (and if possible configurable, as indicated above) :

**Describe the solution you'd like**
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**Describe alternatives you've considered**
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