feat: Add persistent global notification settings for admin panel

Implement database-backed notification settings that persist across restarts:

Backend changes:
- Updated DashboardService to read/write notification settings from database
- Added 6 notification settings keys to dbSettingsMap:
  * enable_email_notifications (boolean)
  * enable_push_notifications (boolean)
  * admin_notifications (boolean)
  * error_alerts (boolean)
  * new_user_alerts (boolean)
  * system_health_alerts (boolean)
- Settings are now retrieved from database with fallback defaults

Database:
- Seeded 6 default notification settings in settings table
- All notification toggles default to 'true'
- Settings persist across server restarts

Frontend:
- Admin settings page at /settings already configured
- Notifications tab contains all 6 toggle switches
- Settings are loaded from GET /api/v1/admin/dashboard/settings
- Settings are saved via POST /api/v1/admin/dashboard/settings

API Endpoints (already existed, now enhanced):
- GET /api/v1/admin/dashboard/settings - Returns all settings including notifications
- POST /api/v1/admin/dashboard/settings - Persists notification settings to database

Files modified:
- maternal-app-backend/src/modules/admin/dashboard/dashboard.service.ts

Benefits:
✅ Global notification settings are now persistent
✅ Admin can control email/push notifications globally
✅ Admin can configure alert preferences
✅ Settings survive server restarts and deployments

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

maternal-web/components/PushNotificationToggle.tsx

@@ -0,0 +1,214 @@
+'use client';
+
+import React, { useState, useEffect } from 'react';
+import { useAuth } from '../contexts/AuthContext';
+import {
+  isPushNotificationSupported,
+  getNotificationPermission,
+  subscribeToPush,
+  unsubscribeFromPush,
+  isPushSubscribed,
+  sendTestPushNotification,
+} from '../lib/push-notifications';
+
+export default function PushNotificationToggle() {
+  const { user, token } = useAuth();
+  const [isSupported, setIsSupported] = useState(false);
+  const [isSubscribed, setIsSubscribed] = useState(false);
+  const [permission, setPermission] = useState<NotificationPermission>('default');
+  const [isLoading, setIsLoading] = useState(false);
+  const [error, setError] = useState<string | null>(null);
+
+  useEffect(() => {
+    checkPushSupport();
+    checkSubscriptionStatus();
+  }, []);
+
+  const checkPushSupport = () => {
+    const supported = isPushNotificationSupported();
+    setIsSupported(supported);
+    if (supported) {
+      setPermission(getNotificationPermission());
+    }
+  };
+
+  const checkSubscriptionStatus = async () => {
+    try {
+      const subscribed = await isPushSubscribed();
+      setIsSubscribed(subscribed);
+    } catch (error) {
+      console.error('Error checking subscription status:', error);
+    }
+  };
+
+  const handleToggle = async () => {
+    if (!token) {
+      setError('You must be logged in to enable notifications');
+      return;
+    }
+
+    setIsLoading(true);
+    setError(null);
+
+    try {
+      if (isSubscribed) {
+        // Unsubscribe
+        await unsubscribeFromPush(token);
+        setIsSubscribed(false);
+        setPermission(getNotificationPermission());
+
+        // Update user preferences to disable push
+        await savePreference(token, false);
+      } else {
+        // Subscribe
+        await subscribeToPush(token);
+        setIsSubscribed(true);
+        setPermission('granted');
+
+        // Update user preferences to enable push
+        await savePreference(token, true);
+      }
+    } catch (err: any) {
+      console.error('Error toggling push notifications:', err);
+      setError(err.message || 'Failed to update notification settings');
+    } finally {
+      setIsLoading(false);
+    }
+  };
+
+  const savePreference = async (authToken: string, enabled: boolean) => {
+    try {
+      const apiUrl = process.env.NEXT_PUBLIC_API_URL || 'http://maternal-api.noru1.ro';
+      const response = await fetch(`${apiUrl}/api/v1/preferences/notifications`, {
+        method: 'PUT',
+        headers: {
+          'Content-Type': 'application/json',
+          'Authorization': `Bearer ${authToken}`,
+        },
+        body: JSON.stringify({
+          pushEnabled: enabled,
+        }),
+      });
+
+      if (!response.ok) {
+        throw new Error('Failed to save preference');
+      }
+
+      console.log('[Push] Preference saved:', enabled);
+    } catch (error) {
+      console.error('[Push] Error saving preference:', error);
+      // Don't throw - subscription still works even if preference save fails
+    }
+  };
+
+  const handleTestNotification = async () => {
+    if (!token) {
+      setError('You must be logged in to send test notifications');
+      return;
+    }
+
+    setIsLoading(true);
+    setError(null);
+
+    try {
+      await sendTestPushNotification(token);
+      // Show success message (you could use a toast/snackbar here)
+      alert('Test notification sent! Check your notifications.');
+    } catch (err: any) {
+      console.error('Error sending test notification:', err);
+      setError(err.message || 'Failed to send test notification');
+    } finally {
+      setIsLoading(false);
+    }
+  };
+
+  if (!isSupported) {
+    return (
+      <div className="bg-yellow-50 dark:bg-yellow-900/20 border border-yellow-200 dark:border-yellow-800 rounded-lg p-4">
+        <p className="text-sm text-yellow-800 dark:text-yellow-200">
+          Push notifications are not supported in your browser. Please use a modern browser like
+          Chrome, Firefox, Edge, or Safari.
+        </p>
+      </div>
+    );
+  }
+
+  return (
+    <div className="space-y-4">
+      <div className="flex items-center justify-between">
+        <div className="flex-1">
+          <h3 className="text-lg font-medium text-gray-900 dark:text-white">
+            Push Notifications
+          </h3>
+          <p className="text-sm text-gray-500 dark:text-gray-400">
+            Get notified about feeding times, diaper changes, and more
+          </p>
+        </div>
+        <button
+          onClick={handleToggle}
+          disabled={isLoading || !user}
+          className={`
+            relative inline-flex h-6 w-11 flex-shrink-0 cursor-pointer rounded-full border-2 border-transparent
+            transition-colors duration-200 ease-in-out focus:outline-none focus:ring-2 focus:ring-primary-500 focus:ring-offset-2
+            disabled:opacity-50 disabled:cursor-not-allowed
+            ${isSubscribed ? 'bg-primary-600' : 'bg-gray-200 dark:bg-gray-700'}
+          `}
+          role="switch"
+          aria-checked={isSubscribed}
+        >
+          <span className="sr-only">Enable push notifications</span>
+          <span
+            className={`
+              pointer-events-none inline-block h-5 w-5 transform rounded-full bg-white shadow ring-0
+              transition duration-200 ease-in-out
+              ${isSubscribed ? 'translate-x-5' : 'translate-x-0'}
+            `}
+          />
+        </button>
+      </div>
+
+      {error && (
+        <div className="bg-red-50 dark:bg-red-900/20 border border-red-200 dark:border-red-800 rounded-lg p-3">
+          <p className="text-sm text-red-800 dark:text-red-200">{error}</p>
+        </div>
+      )}
+
+      {permission === 'denied' && (
+        <div className="bg-orange-50 dark:bg-orange-900/20 border border-orange-200 dark:border-orange-800 rounded-lg p-3">
+          <p className="text-sm text-orange-800 dark:text-orange-200">
+            Notifications are blocked. Please enable them in your browser settings and reload the
+            page.
+          </p>
+        </div>
+      )}
+
+      {isSubscribed && (
+        <div className="space-y-2">
+          <div className="bg-green-50 dark:bg-green-900/20 border border-green-200 dark:border-green-800 rounded-lg p-3">
+            <p className="text-sm text-green-800 dark:text-green-200">
+              ✓ You&apos;re subscribed to push notifications
+            </p>
+          </div>
+          <button
+            onClick={handleTestNotification}
+            disabled={isLoading}
+            className="
+              w-full sm:w-auto px-4 py-2 text-sm font-medium text-primary-700 dark:text-primary-300
+              bg-primary-50 dark:bg-primary-900/20 hover:bg-primary-100 dark:hover:bg-primary-900/30
+              rounded-lg transition-colors disabled:opacity-50 disabled:cursor-not-allowed
+            "
+          >
+            Send Test Notification
+          </button>
+        </div>
+      )}
+
+      {isLoading && (
+        <div className="flex items-center justify-center py-2">
+          <div className="animate-spin rounded-full h-5 w-5 border-b-2 border-primary-600"></div>
+          <span className="ml-2 text-sm text-gray-600 dark:text-gray-400">Processing...</span>
+        </div>
+      )}
+    </div>
+  );
+}