Bugs:
- ConfigPanel (CB1): unchecking a Plex library from the "all" (empty) state made
that library the ONLY selected one instead of all-except-it, because the toggle
ADDED the key to an empty list. Expand "all" to the explicit section set before
toggling. E2E-verified: uncheck from all → all-except-one.
- Scheduler (SB1): "Purge discovery" bulk-deleted search videos/videos/channels
immediately with no confirm (every AdminUsers destructive action uses useConfirm).
Wrapped in a danger useConfirm dialog (+ trilingual purgeConfirmTitle key).
E2E-verified: dialog appears, Cancel aborts.
Cleanups (behavior-neutral):
- Register LS.configTab; ConfigPanel uses it instead of the bare "siftlode.configTab".
- ConfigPanel + SettingsPanel import SaveState from ui/DraftSaveBar instead of
redeclaring the union (PrefsSaveState is now an alias).
tsc green, re-review clean, localdev boots.