When a tariff has a stale external_squad_uuid that no longer exists in
the Remnawave panel, PATCH/POST /api/users fails with A039 (P2003 FK
constraint violation). This caused subscriptions to not sync with the
panel even though balance was already charged.
Now both update_user() and create_user() catch A039 errors and
automatically retry without externalSquadUuid, logging a warning about
the stale UUID. The subscription sync succeeds without the external
squad assignment rather than failing entirely.
Fringg
de00612965