Feat: add "detail" row in notifications table migration
This makes searching for specific notifications in the
code like cashbox number easier because we don't need
to scrub the notification message column anymore to search
for notifications relating the cashbox 1 for example.
Feat: clear notifications on cash cassette balance update
A TX on the 'rejected' state should still be watched for authorization.
This fixes the bug where delayed cash-out confirmations would not
trigger a exchange sell command.
