Add AI-powered mental wellness features: Reflection Companion, Pattern Tags, Weekly Digest

Three new Foundation Models features to deepen user engagement with mental wellness:

1. AI Reflection Companion — personalized feedback after completing guided reflections,
   referencing the user's actual words with personality-pack-adapted tone
2. Mood Pattern Tags — auto-extracts theme tags (work, family, stress, etc.) from notes
   and reflections, displayed as colored pills on entries
3. Weekly Emotional Digest — BGTask-scheduled Sunday digest with headline, summary,
   highlight, and intention; shown as card in Insights tab with notification

All features: on-device (zero cost), premium-gated, iOS 26+ with graceful degradation.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Shared/LocalNotification.swift

@@ -135,6 +135,28 @@ class LocalNotification {
 
     // MARK: - Debug: Send All Personality Pack Notifications
 
+    // MARK: - Weekly Digest Notification
+
+    public class func scheduleDigestNotification(headline: String, personalityPack: PersonalityPack) {
+        let content = UNMutableNotificationContent()
+        content.title = String(localized: "Your Weekly Digest")
+        content.body = headline
+        content.sound = .default
+
+        let trigger = UNTimeIntervalNotificationTrigger(timeInterval: 1, repeats: false)
+        let request = UNNotificationRequest(
+            identifier: "weekly-digest-\(UUID().uuidString)",
+            content: content,
+            trigger: trigger
+        )
+
+        UNUserNotificationCenter.current().add(request) { error in
+            if let error = error {
+                print("Failed to schedule digest notification: \(error)")
+            }
+        }
+    }
+
     #if DEBUG
     /// Sends one notification from each personality pack, staggered over 10 seconds for screenshot
     public class func sendAllPersonalityNotificationsForScreenshot() {