Redesign workout live activity with circular timer ring, phase icons, and smoother updates

- Add CountdownRing with real-time arc progress on lock screen
- Replace generic dots with phase-specific SF Symbols (flame, snowflake, etc.)
- Remove horizontal progress bar in favor of round counter text
- Increase Dynamic Island expanded font sizes for better visibility
- Increase live activity sync frequency from 5s to 1s for smoother arc updates
- Add pause/resume button via TogglePauseIntent AppIntent
- Remove AlertConfiguration to silence notification sounds on updates

tabatago-swift/TabataGo/Models/WorkoutActivityAttributes.swift

@@ -40,6 +40,7 @@ struct WorkoutActivityAttributes: ActivityAttributes {
         var exerciseName: String
         var phase: WorkoutPhase
         var phaseEndDate: Date
+        var phaseDuration: TimeInterval
         var roundCurrent: Int
         var roundTotal: Int
         var heartRate: Double

tabatago-swift/TabataGo/ViewModels/PlayerViewModel.swift

@@ -365,7 +365,7 @@ final class PlayerViewModel: ObservableObject {
 
     // ─── Dynamic Island / Live Activity ─────────────────────────────
 
-    func syncActivity() {
+    func syncActivity(shouldAlert: Bool = false) {
         guard ActivityAuthorizationInfo().areActivitiesEnabled else { return }
         guard isRunning else { return }
 
@@ -377,6 +377,7 @@ final class PlayerViewModel: ObservableObject {
             exerciseName: currentExercise?.nameEn ?? "",
             phase: workoutPhase,
             phaseEndDate: phaseEnd,
+            phaseDuration: Double(totalPhaseTime),
             roundCurrent: currentRound,
             roundTotal: totalRoundsInBlock,
             heartRate: heartRate,
@@ -393,7 +394,7 @@ final class PlayerViewModel: ObservableObject {
         if let existing = workoutActivity {
             nonisolated(unsafe) let safeExisting = existing
             let staleDate = Date().addingTimeInterval(isPaused ? 3600 : 120)
-            let alert = alertForPhase(workoutPhase)
+            let alert = shouldAlert ? alertForPhase(workoutPhase) : nil
             Task { @MainActor in
                 if let alert {
                     await safeExisting.update(ActivityContent(state: state, staleDate: staleDate), alertConfiguration: alert)
@@ -444,6 +445,7 @@ final class PlayerViewModel: ObservableObject {
             exerciseName: safeActivity.content.state.exerciseName,
             phase: .complete,
             phaseEndDate: safeActivity.content.state.phaseEndDate,
+            phaseDuration: safeActivity.content.state.phaseDuration,
             roundCurrent: safeActivity.content.state.roundCurrent,
             roundTotal: safeActivity.content.state.roundTotal,
             heartRate: safeActivity.content.state.heartRate,
@@ -457,7 +459,7 @@ final class PlayerViewModel: ObservableObject {
 
     private func startActivitySyncTimer() {
         stopActivitySyncTimer()
-        activitySyncTimer = Timer.scheduledTimer(withTimeInterval: 5.0, repeats: true) { [weak self] _ in
+        activitySyncTimer = Timer.scheduledTimer(withTimeInterval: 1.0, repeats: true) { [weak self] _ in
             Task { @MainActor [weak self] in
                 self?.syncActivity()
             }