Fix all NotificationManager concurrency warnings

- Remove @MainActor from class (caused all Sendable/isolation cascade)
- Keep @MainActor only on reschedule() where VM access is needed
- Snapshot tasks in reschedule() so scheduleTasks() never captures
  a non-Sendable TaskViewModel across async boundaries
- Capture center locally in scheduleTasks() to avoid @MainActor
  property access inside the @Sendable getPendingNotificationRequests callback
- Mark UNUserNotificationCenterDelegate methods nonisolated to satisfy
  protocol conformance without actor crossing

Co-Authored-By: Kutesir <tqwyy79vzn@privaterelay.appleid.com>

KisaniCal/Managers/NotificationManager.swift

@@ -36,11 +36,13 @@ final class NotificationManager: NSObject, ObservableObject {
 
     // MARK: - Reschedule (call on foreground + state changes)
 
+    @MainActor
     func reschedule(workoutVM: WorkoutViewModel, taskVM: TaskViewModel) {
-        // Snapshot @MainActor-isolated values before the async boundary
+        // Snapshot all @MainActor-isolated values before the async boundary
         let schedule  = workoutVM.schedule
         let programs  = workoutVM.programs
         let progress  = workoutVM.progress
+        let tasks     = taskVM.tasks
 
         center.getNotificationSettings { [weak self] settings in
             guard let self else { return }
@@ -48,7 +50,7 @@ final class NotificationManager: NSObject, ObservableObject {
                   || settings.authorizationStatus == .provisional
             guard ok else { return }
             self.scheduleWorkout(schedule: schedule, programs: programs, progress: progress)
-            self.scheduleTasks(taskVM)
+            self.scheduleTasks(snapshot: tasks)
         }
     }
 
@@ -71,7 +73,6 @@ final class NotificationManager: NSObject, ObservableObject {
             guard let program = programs.first(where: { $0.id == pid }) else { continue }
             let doneToday = weekday == todayWD && progress >= 1.0
 
-            // Pre-workout reminder
             if reminderOn && !doneToday {
                 let content = UNMutableNotificationContent()
                 content.title    = program.name
@@ -87,7 +88,6 @@ final class NotificationManager: NSObject, ObservableObject {
                 ))
             }
 
-            // Post-workout check-in
             if checkInOn {
                 let content = UNMutableNotificationContent()
                 content.title    = "\(program.name) — check in"
@@ -107,9 +107,8 @@ final class NotificationManager: NSObject, ObservableObject {
 
     // MARK: - Per-task reminders + evening check-in
 
-    private func scheduleTasks(_ taskVM: TaskViewModel) {
+    private func scheduleTasks(snapshot: [TaskItem]) {
-        // Capture on the calling thread (main) before crossing into the async callback
+        let center = self.center
-        let snapshot = taskVM.tasks
 
         center.getPendingNotificationRequests { [weak self] pending in
             guard let self else { return }
@@ -117,8 +116,8 @@ final class NotificationManager: NSObject, ObservableObject {
             let oldTaskIds = pending
                 .filter { $0.identifier.hasPrefix("kisani.task.") }
                 .map { $0.identifier }
-            self.center.removePendingNotificationRequests(withIdentifiers: oldTaskIds)
+            center.removePendingNotificationRequests(withIdentifiers: oldTaskIds)
-            self.center.removePendingNotificationRequests(withIdentifiers: [self.tasksId])
+            center.removePendingNotificationRequests(withIdentifiers: [self.tasksId])
 
             let now = Date()
             let cal = Calendar.current
@@ -143,14 +142,13 @@ final class NotificationManager: NSObject, ObservableObject {
                 content.userInfo = ["taskId": task.id.uuidString, "deeplink": "tasks"]
 
                 let trigComps = cal.dateComponents([.year, .month, .day, .hour, .minute], from: fireDate)
-                let trigger = UNCalendarNotificationTrigger(dateMatching: trigComps, repeats: false)
+                center.add(UNNotificationRequest(
-                self.center.add(UNNotificationRequest(
                     identifier: "kisani.task.\(task.id.uuidString)",
-                    content: content, trigger: trigger
+                    content: content,
+                    trigger: UNCalendarNotificationTrigger(dateMatching: trigComps, repeats: false)
                 ))
             }
 
-            // Evening urgent check-in
             let count = snapshot.filter { !$0.isComplete && $0.quadrant == .urgent }.count
             guard count > 0 else { return }
             let ec = UNMutableNotificationContent()
@@ -159,8 +157,11 @@ final class NotificationManager: NSObject, ObservableObject {
             ec.sound = .default
             ec.userInfo = ["deeplink": "tasks"]
             var eComps = DateComponents(); eComps.hour = 19; eComps.minute = 30
-            let eTrigger = UNCalendarNotificationTrigger(dateMatching: eComps, repeats: true)
+            center.add(UNNotificationRequest(
-            self.center.add(UNNotificationRequest(identifier: self.tasksId, content: ec, trigger: eTrigger))
+                identifier: self.tasksId,
+                content: ec,
+                trigger: UNCalendarNotificationTrigger(dateMatching: eComps, repeats: true)
+            ))
         }
     }
 
@@ -177,8 +178,7 @@ final class NotificationManager: NSObject, ObservableObject {
 // MARK: - UNUserNotificationCenterDelegate
 
 extension NotificationManager: UNUserNotificationCenterDelegate {
-    // Show banners even when app is foregrounded
+    nonisolated func userNotificationCenter(
-    func userNotificationCenter(
         _ center: UNUserNotificationCenter,
         willPresent notification: UNNotification,
         withCompletionHandler completionHandler: @escaping (UNNotificationPresentationOptions) -> Void
@@ -186,7 +186,7 @@ extension NotificationManager: UNUserNotificationCenterDelegate {
         completionHandler([.banner, .sound, .list, .badge])
     }
 
-    func userNotificationCenter(
+    nonisolated func userNotificationCenter(
         _ center: UNUserNotificationCenter,
         didReceive response: UNNotificationResponse,
         withCompletionHandler completionHandler: @escaping () -> Void