sort is gorm:"size:4", which MySQL builds as a tinyint holding -128..127.
The demo menu seeded Sort: 900, so on MySQL the run stopped at
1786700001000 with Error 1264, and every migration after it - including
the soft-delete conversion - never ran.
deleted_at therefore stayed NULL while the code queries deleted_at = 0,
and the login returned 'incorrect Username or Password' on a database
whose password hash was correct all along.
sqlite ignores the declared width, so a fresh install there passed and
the fault only appeared on MySQL.