fix: Dynamic Island, Live Activity errors, background audio stop, CFBundleVersion

Phase 1 — Audio background resilience:
- Remove .mixWithOthers, app takes audio focus for coach cues
- Add AVAudioSession.interruptionNotification handler (re-activates after calls/Siri)
- Add AVAudioSession.routeChangeNotification handler (re-activates on headphone changes)

Phase 2 — Live Activity error surfacing:
- PlayerViewModel: @Published liveActivityError captures auth-denied + request errors
- PlayerView: translucent error banner with dismiss button (non-blocking)

Phase 3 — CFBundleVersion 1→2 in all 4 Info.plist files (match project.yml CURRENT_PROJECT_VERSION: 2)

tabatago-swift/TabataGo/Resources/Info.plist

@@ -28,7 +28,7 @@
 		</dict>
 	</array>
 	<key>CFBundleVersion</key>
-	<string>1</string>
+	<string>2</string>
 	<key>NSHealthShareUsageDescription</key>
 	<string>TabataGo reads your health data to show fitness stats and personalize your workouts.</string>
 	<key>NSHealthUpdateUsageDescription</key>

tabatago-swift/TabataGo/Services/AudioService.swift

@@ -28,12 +28,55 @@ final class AudioService {
             try audioSession.setCategory(
                 .playback,
                 mode: .default,
-                options: [.mixWithOthers, .allowAirPlay, .allowBluetooth]
+                options: [.allowAirPlay, .allowBluetooth]
             )
             try audioSession.setActive(true)
         } catch {
             print("[Audio] Session configuration failed: \(error)")
         }
+
+        // ─── Interruption Handler
+        NotificationCenter.default.addObserver(
+            forName: AVAudioSession.interruptionNotification,
+            object: nil,
+            queue: .main
+        ) { [weak self] notification in
+            guard let self,
+                  let typeValue = notification.userInfo?[AVAudioSessionInterruptionTypeKey] as? UInt,
+                  let type = AVAudioSession.InterruptionType(rawValue: typeValue) else { return }
+
+            if type == .ended {
+                guard let optionsValue = notification.userInfo?[AVAudioSessionInterruptionOptionKey] as? UInt,
+                      AVAudioSession.InterruptionOptions(rawValue: optionsValue).contains(.shouldResume) else { return }
+                do {
+                    try self.audioSession.setActive(true)
+                } catch {
+                    print("[Audio] Re-activation failed after interruption: \(error)")
+                }
+            }
+        }
+
+        // ─── Route Change Handler
+        NotificationCenter.default.addObserver(
+            forName: AVAudioSession.routeChangeNotification,
+            object: nil,
+            queue: .main
+        ) { [weak self] notification in
+            guard let self,
+                  let reasonValue = notification.userInfo?[AVAudioSessionRouteChangeReasonKey] as? UInt,
+                  let reason = AVAudioSession.RouteChangeReason(rawValue: reasonValue) else { return }
+
+            switch reason {
+            case .newDeviceAvailable, .oldDeviceUnavailable:
+                do {
+                    try self.audioSession.setActive(true)
+                } catch {
+                    print("[Audio] Route re-activation failed: \(error)")
+                }
+            default:
+                break
+            }
+        }
     }
 
     // ─── Phase Audio Cues ─────────────────────────────────────────

tabatago-swift/TabataGo/ViewModels/PlayerViewModel.swift

@@ -39,6 +39,7 @@ final class PlayerViewModel: ObservableObject {
     @Published var isComplete: Bool = false
     @Published var showExitConfirmation: Bool = false
     @Published private(set) var completedSession: WorkoutSession? = nil
+    @Published var liveActivityError: String? = nil
 
     // Track info for Live Activity — set by View when music changes
     var currentTrackTitle = ""
@@ -382,7 +383,10 @@ final class PlayerViewModel: ObservableObject {
     // ─── Dynamic Island / Live Activity ─────────────────────────────
 
     func syncActivity(shouldAlert: Bool = false) {
-        guard ActivityAuthorizationInfo().areActivitiesEnabled else { return }
+        guard ActivityAuthorizationInfo().areActivitiesEnabled else {
+            liveActivityError = "Live Activities are disabled in Settings"
+            return
+        }
         guard isRunning else { return }
 
         let isPlayingMusic = (phase == .work || phase == .rest) && isRunning && !isPaused
@@ -449,8 +453,10 @@ final class PlayerViewModel: ObservableObject {
                 attributes: attrs,
                 content: ActivityContent(state: state, staleDate: staleDate)
             )
+            liveActivityError = nil
             observeActivityState()
         } catch {
+            liveActivityError = error.localizedDescription
             print("❌ Failed to start Live Activity: \(error.localizedDescription)")
         }
     }

tabatago-swift/TabataGo/Views/Player/PlayerView.swift

@@ -66,6 +66,40 @@ struct PlayerView: View {
                     }
                 }
 
+                // ══════════════════════════════════════════════════
+                // Live Activity error banner (non-blocking)
+                // ══════════════════════════════════════════════════
+                if let error = vm.liveActivityError {
+                    VStack {
+                        HStack(spacing: 8) {
+                            Image(systemName: "exclamationmark.triangle.fill")
+                                .font(.caption)
+                                .foregroundStyle(.yellow)
+                            Text(error)
+                                .font(.caption2.weight(.medium))
+                                .foregroundStyle(.white.opacity(0.9))
+                            Spacer()
+                            Button {
+                                vm.liveActivityError = nil
+                            } label: {
+                                Image(systemName: "xmark")
+                                    .font(.system(size: 10, weight: .bold))
+                                    .foregroundStyle(.white.opacity(0.6))
+                            }
+                        }
+                        .padding(.horizontal, 16)
+                        .padding(.vertical, 10)
+                        .background(.ultraThinMaterial.opacity(0.9))
+                        .clipShape(RoundedRectangle(cornerRadius: 12))
+                        .padding(.horizontal, 16)
+                        .padding(.top, 60)
+                        Spacer()
+                    }
+                    .transition(.move(edge: .top).combined(with: .opacity))
+                    .animation(.spring(duration: 0.3), value: vm.liveActivityError)
+                    .zIndex(100)
+                }
+
                 // ══════════════════════════════════════════════════
                 // Layer 4 — Compact timer ring (top-right corner)
                 // ══════════════════════════════════════════════════