Show only the day's docket on the Today board and add ad hoc Now workouts

- Due-filter schedules: daily always, fixed days by weekday, one-offs on
  their date; rest days get an empty state
- Workouts with no due schedule row (ad hoc or off-day starts) now render
  as their own board rows
- The + sheet is now "New Workout" with a "When" picker; "Now" (offered
  when adding on today) skips the schedule and starts the workout directly
- Remove the times-per-week scheduling mode everywhere (enum, document,
  entity, mappers, planner, seeds, tests)

Workouts/Views/Progress/ProgressTabView.swift

@@ -70,7 +70,6 @@ struct ProgressTabView: View {
                 goal: schedule.goalKind,
                 recurrence: schedule.recurrenceEnum,
                 weekdays: schedule.weekdays,
-                timesPerWeek: schedule.timesPerWeek,
                 onceDate: schedule.date,
                 createdAt: schedule.createdAt,
                 routineID: sync.currentRoutineID(for: schedule.routineID),