Open new workouts directly and improve accessibility

Starting a workout — from the split picker or a split's exercise list —
now drops straight into its log screen once the cache catches up, via a
shared StartedWorkoutNavigator. Adds VoiceOver labels/values to the log
checkboxes and the settings button, a color-independent numbered legend
and spoken summary to the heart-rate-zone bar, and Dynamic Type scaling
to the run-flow badges and timer.

Claude-Session: https://claude.ai/code/session_01HJDQQDA9QdP8zByg43H5v3

Workouts/Views/Common/CalendarListItem.swift

@@ -32,6 +32,9 @@ struct CalendarListItem: View {
                 }
                 .padding([.trailing], 10)
             }
+            // Read the date as one phrase instead of three disjoint "Mon" / "14" / "Jul" stops.
+            .accessibilityElement(children: .ignore)
+            .accessibilityLabel(date.formatted(date: .complete, time: .omitted))
             HStack(alignment: .top) {
                 VStack(alignment: .leading) {
                     Text(title)