Link event staffing shifts to ticketed events with auto pre-fill

Shift.ticketedEventId (nullable FK to TicketedEvent) persists the
link between a staffing shift and its parent event. The shift list
response now includes the linked event (id, slug, title, date) so
the admin UI can show context without a second request.

The Create/Edit Shift drawer gains a conditional Event picker that
only appears when kind is EVENT_STAFFING. Picking an event pre-fills
the form's date, startTime, endTime, and location (venue name +
address) — and seeds the title with "Staff: {event.title}" only if
the title field is still empty, so hand-typed overrides aren't
stomped. Switching kind away from EVENT_STAFFING clears the link.

The shifts table's Kind tag wraps in a tooltip showing the linked
event title when one is present, so organizers can see at a glance
which staffing shifts belong to which event without opening the
drawer.

Bunker Admin

api/prisma/migrations/20260411120000_shift_event_link/migration.sql

@@ -0,0 +1,7 @@
+
+-- AlterTable
+ALTER TABLE "shifts" ADD COLUMN     "ticketed_event_id" TEXT;
+
+-- AddForeignKey
+ALTER TABLE "shifts" ADD CONSTRAINT "shifts_ticketed_event_id_fkey" FOREIGN KEY ("ticketed_event_id") REFERENCES "ticketed_events"("id") ON DELETE SET NULL ON UPDATE CASCADE;
+

api/prisma/schema.prisma

@@ -876,6 +876,10 @@ model Shift {
   cutId             String?
   cut               Cut?        @relation(fields: [cutId], references: [id], onDelete: SetNull)
 
+  // Event linkage (EVENT_STAFFING shifts)
+  ticketedEventId String?        @map("ticketed_event_id")
+  ticketedEvent   TicketedEvent? @relation("EventStaffingShifts", fields: [ticketedEventId], references: [id], onDelete: SetNull)
+
   // Repeating shift series
   seriesId    String?
   series      ShiftSeries? @relation(fields: [seriesId], references: [id], onDelete: SetNull)
@@ -5009,11 +5013,12 @@ model TicketedEvent {
   updatedAt DateTime @updatedAt @map("updated_at")
 
   // Relations
-  createdBy   User         @relation("EventCreator", fields: [createdByUserId], references: [id])
-  meeting     Meeting?     @relation("EventMeeting", fields: [meetingId], references: [id], onDelete: SetNull)
-  ticketTiers TicketTier[] @relation("EventTiers")
-  tickets     Ticket[]     @relation("EventTickets")
-  checkIns    CheckIn[]    @relation("EventCheckIns")
+  createdBy      User         @relation("EventCreator", fields: [createdByUserId], references: [id])
+  meeting        Meeting?     @relation("EventMeeting", fields: [meetingId], references: [id], onDelete: SetNull)
+  ticketTiers    TicketTier[] @relation("EventTiers")
+  tickets        Ticket[]     @relation("EventTickets")
+  checkIns       CheckIn[]    @relation("EventCheckIns")
+  staffingShifts Shift[]      @relation("EventStaffingShifts")
 
   @@index([status], map: "idx_ticketed_events_status")
   @@index([date], map: "idx_ticketed_events_date")