Deleting any device whose stats rows still referenced it failed with
500: reading_history.device_id is a NO-ACTION FK by design (the rows
are real captured reading stats — Users reads them), so a blind DELETE
violated the constraint. Surfaced by the Android app's new logout
deregister call, but the admin Devices page Deletes hit the same stone.
Fix: DetachReadingHistoryFromDevice — NULL the device association on
the user's history rows before the device DELETE (single handler
pass). device_id is nullable; the stats survive, the device frees its
identifier. sqlc regenerated.
John O'Keefe
d49a9e6ca2