Jellyfin never consults IsAdministrator when authorizing a library
delete: BaseItem.IsAuthorizedToDelete looks at EnableContentDeletion and
the per-library grant, and only the first user a server creates gets the
former for free. Gating the "Delete from server" entry on the admin bit
therefore offered a destructive action that answers 401 to later
administrators, and hid it from plain users who do hold the grant.
Ask the server per item instead, through the new
MediaDeletionPermissionClient capability: BaseItemDto.CanDelete already
folds the global grant, the per-library grant, and item state such as
missing files or an in-progress recording. The probe runs when a menu
opens on a deletable kind, costs ~0.5 KB, carries a whole-request
deadline because the client's own budget covers connect and receive
separately, and fails closed on anything unknown. Plex keeps its
account-level owner/admin gate; it has no per-item permission on the
wire.
close#1749
Introduces shared seams for paginated views, D-pad reorder, media control
routing, async singletons and the device method channel, then points the
open-coded copies at them.
Also removes unused models and duplicated provider/server plumbing, folds
the twice-implemented artifact store in the server, and factors the
repeated Flutter toolchain prologue in CI into a composite action.
edde746