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)

Shared/Model/Entities.swift

@@ -317,7 +317,6 @@ final class Schedule {
     var goalRaw: String?
     var recurrenceRaw: String = ScheduleRecurrence.daily.rawValue
     var weekdays: [Int]?
-    var timesPerWeek: Int?
     var date: Date?
     var order: Int = 0
     var createdAt: Date = Date()
@@ -325,7 +324,7 @@ final class Schedule {
     var jsonRelativePath: String = ""
 
     init(id: String, routineID: String, routineName: String, goalRaw: String?,
-         recurrenceRaw: String, weekdays: [Int]?, timesPerWeek: Int?, date: Date? = nil,
+         recurrenceRaw: String, weekdays: [Int]?, date: Date? = nil,
          order: Int, createdAt: Date, updatedAt: Date, jsonRelativePath: String) {
         self.id = id
         self.routineID = routineID
@@ -333,7 +332,6 @@ final class Schedule {
         self.goalRaw = goalRaw
         self.recurrenceRaw = recurrenceRaw
         self.weekdays = weekdays
-        self.timesPerWeek = timesPerWeek
         self.date = date
         self.order = order
         self.createdAt = createdAt
@@ -352,8 +350,8 @@ final class Schedule {
     }
 
     /// Human-readable recurrence line — shares its formatting with `ScheduleDocument`
-    /// via `ScheduleRecurrence.summary(weekdays:timesPerWeek:date:)`.
+    /// via `ScheduleRecurrence.summary(weekdays:date:)`.
     var recurrenceSummary: String {
-        recurrenceEnum.summary(weekdays: weekdays, timesPerWeek: timesPerWeek, date: date)
+        recurrenceEnum.summary(weekdays: weekdays, date: date)
     }
 }