Remove ungrouped devices panel

[murrant]

The panel destroyed the page performance on larger installs.
Now has a link to the devices list with new group=none

Please note

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Testers

If you would like to test this pull request then please run: ./scripts/github-apply <pr_id>, i.e ./scripts/github-apply 5926
After you are done testing, you can remove the changes with ./scripts/github-remove. If there are schema changes, you can ask on discord how to revert.