Add full notification preferences system

Users can now control which in-app and email notifications they receive
from their Settings tab on their channel page.

Bell (in-app) preferences:
- New comment on my video (default: on)
- Reply to my comment (default: on)
- Comment liked (default: on)
- Video liked (default: on)
- New subscriber (default: on)
- New video from channels I follow (default: on)
- New post from channels I follow (default: on)
- New user registration — super admins only (default: on)

Email preferences (same set plus):
- Comment liked (default: off — too noisy)
- Video liked (default: off — too noisy)
- New post from channels I follow (default: off)
- My video finished processing (default: on)
- Weekly activity digest every Monday (default: on)
- New user registration — super admins only (default: on)

Implementation:
- Migration: notification_preferences JSON column on users table
- User::notificationPref($key) helper with typed defaults
- All existing notification classes updated to check prefs in via()
- 4 new notification classes: NewSubscriberNotification,
  VideoLikedNotification, NewPostNotification, WeeklyDigestNotification
- 8 new email views matching existing dark theme
- SendWeeklyDigest artisan command, scheduled every Monday 09:00
- NewSubscriberNotification wired into UserController::toggleSubscribe
- VideoLikedNotification wired into UserController::toggleLike
- NewPostNotification wired into PostController::store (to all subscribers)
- Bell renderer updated for new_subscriber, video_like, new_post types
- Preferences saved via AJAX (POST /settings/notifications) — instant
  toggle with automatic revert on failure

Co-Authored-By: Claude Sonnet 4.6 <[email protected]>

app/Http/Controllers/UserController.php

@@ -7,6 +7,8 @@ use App\Models\AuditLog;
 use App\Models\Post;
 use App\Models\User;
 use App\Models\Video;
+use App\Notifications\NewSubscriberNotification;
+use App\Notifications\VideoLikedNotification;
 use Illuminate\Http\Request;
 use Illuminate\Support\Facades\Auth;
 use Illuminate\Support\Facades\Hash;
@@ -151,6 +153,22 @@ class UserController extends Controller
         return redirect()->route('channel')->with('toast_success', 'Password updated!')->with('_open_tab', 'settings');
     }
 
+    // Save a single notification preference toggle (AJAX)
+    public function updateNotificationPreferences(Request $request)
+    {
+        $request->validate([
+            'key'   => ['required', 'string', 'in:' . implode(',', array_keys(User::notifDefaults()))],
+            'value' => ['required', 'boolean'],
+        ]);
+
+        $user  = Auth::user();
+        $prefs = $user->notification_preferences ?? [];
+        $prefs[$request->key] = (bool) $request->value;
+        $user->update(['notification_preferences' => $prefs]);
+
+        return response()->json(['ok' => true]);
+    }
+
     // Logout all other devices
     public function logoutAllDevices(Request $request)
     {
@@ -348,6 +366,9 @@ class UserController extends Controller
         } else {
             $video->likes()->attach($user->id);
             $liked = true;
+            if ($video->user_id && $video->user_id !== $user->id) {
+                try { $video->user->notify(new VideoLikedNotification($video, $user)); } catch (\Throwable) {}
+            }
         }
 
         return response()->json([
@@ -370,6 +391,7 @@ class UserController extends Controller
         } else {
             $me->subscriptions()->attach($user->id);
             $subscribed = true;
+            try { $user->notify(new NewSubscriberNotification($me)); } catch (\Throwable) {}
         }
 
         return response()->json([