Bonus payment

[npaton]

• Upload bonus CSV/JSON with 2 fields/columns: mturkWorkerID and bonus in USD
• Create bonus ent schema: run, participant, hitID, assignmentID, stepID, bonus amount, paidAt (timestamp)
• On import, look for last HIT in current run, if none, find last HIT user particpated in (query Participations for hitID exists ordered by desc createAt)
• show table with Worker ID, bonus, paid or not, amount (editable – optional), and a send bonus button at top
• when send bonus clicked, lock table (diable dens bonus button, bonus fields not editable), and SendBonus MTurk API
• mark participants' bonus as paid (refresh page)

[npaton]

Should have a simple graphqlAPI for importing bonus, like pariticpants. addBonus() maybe.