ui: osd: warn if removal could be problematic

ui: osd: warn if removal could be problematic

If an OSD is removed during the wrong conditions, it could lead to
blocked IO or worst case data loss.

Check against global flags that limit the capabilities of Ceph to heal
itself (norebalance, norecover, noout) and if there are degraded
objects.

Unfortunately, the 'safe-to-destroy' Ceph API endpoint will not help
here as it only works as long as the OSD is still running. By the time
the destroy button is enabled, the OSD will already be stopped.

Signed-off-by: Aaron Lauterer <a.lauterer@proxmox.com>