Lost on this Axum error... any thoughts?

Not sure what happened exactly... it was working fine and I didn't change anything in this file. It has to be related to something I did recently:

1. Ran a migration adding a unique constraint on a table
2. Generated two new entities of a couple very basic tables.

The handler I'm using isn't even using the new tables, so I don't know why this randomly broke. Anyone have any ideas? Or even some guidance on how to decipher that obscure error would be helpful.