Update deadline buckets for weekly Thursday assignment rounds

Order deadlines scatter across weeks, leaving production unsure which items need Thursday prep. Deadlines are bucketed into this/next/overdue so coordinators can act ahead of the Thursday cycle.

Overview

Weekly deadline drift causes last-minute firefighting; this flow buckets orders by which Thursday they belong to so production and planners always know what to prepare. Coordinators get clear, actionable buckets within minutes of each scheduled run, reducing scramble before the Thursday assignment.