feat: add notification center with bell dropdown, full page, and workspace scoping (Story 3.3)

Enhance NotificationDropdown with type-specific icons, French description builder,
click-to-navigate with mark-as-read, and "Voir toutes les notifications" link.
Add full notifications page at /notifications with pagination (25/page), individual
mark-as-read, and empty state. Includes code review fixes: workspace-scoped unread
count and dropdown items, race condition fix (mark-as-read before navigate),
efficient markAllAsRead via direct update, deleted declaration URL handling,
and per-workspace cache keys. 7 new feature tests.

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

app/Http/Controllers/NotificationController.php

@@ -2,12 +2,61 @@
 
 namespace App\Http\Controllers;
 
+use App\Concerns\HasWorkspaceScope;
+use App\Models\Declaration;
+use App\Models\User;
 use Illuminate\Http\RedirectResponse;
 use Illuminate\Http\Request;
 use Illuminate\Support\Facades\Cache;
+use Inertia\Inertia;
+use Inertia\Response;
 
 class NotificationController extends Controller
 {
+    use HasWorkspaceScope;
+
+    public function index(Request $request): Response
+    {
+        $workspace = $this->currentWorkspace();
+
+        $notifications = $request->user()
+            ->notifications()
+            ->whereJsonContains('data->workspace_id', $workspace->id)
+            ->latest()
+            ->paginate(25);
+
+        $declarationIds = collect($notifications->items())->pluck('data.declaration_id')->filter()->unique()->values();
+        $senderIds = collect($notifications->items())->pluck('data.sender_id')->filter()->unique()->values();
+
+        $declarations = Declaration::whereIn('id', $declarationIds)->pluck('title', 'id');
+        $senders = User::whereIn('id', $senderIds)->pluck('name', 'id');
+
+        $notifications->through(function ($n) use ($declarations, $senders) {
+            $data = $n->data;
+            $declarationId = $data['declaration_id'] ?? null;
+            $senderId = $data['sender_id'] ?? null;
+
+            $declarationExists = $declarationId && isset($declarations[$declarationId]);
+            $data['declaration_title'] = $declarationExists ? $declarations[$declarationId] : null;
+            $data['sender_name'] = $senderId ? ($senders[$senderId] ?? null) : null;
+            $data['url'] = $declarationExists ? route('declarations.show', $declarationId) : null;
+
+            return [
+                'id' => $n->id,
+                'type' => class_basename($n->type),
+                'data' => $data,
+                'read_at' => $n->read_at?->toISOString(),
+                'created_at' => $n->created_at->diffForHumans(),
+            ];
+        });
+
+        return Inertia::render('notifications/Index', [
+            'notifications' => $notifications,
+            'markAllReadUrl' => route('notifications.readAll'),
+            'readUrl' => route('notifications.read', ['id' => '__ID__']),
+        ]);
+    }
+
     public function markAsRead(Request $request, string $id): RedirectResponse
     {
         $request->user()
@@ -16,16 +65,22 @@ class NotificationController extends Controller
             ->firstOrFail()
             ->markAsRead();
 
-        Cache::forget("user:{$request->user()->id}:unread_notifications");
+        $workspaceId = $request->session()->get('current_workspace_id');
+        Cache::forget("user:{$request->user()->id}:workspace:{$workspaceId}:unread_notifications");
 
         return back();
     }
 
     public function markAllAsRead(Request $request): RedirectResponse
     {
-        $request->user()->unreadNotifications->markAsRead();
+        $workspace = $this->currentWorkspace();
 
-        Cache::forget("user:{$request->user()->id}:unread_notifications");
+        $request->user()
+            ->unreadNotifications()
+            ->whereJsonContains('data->workspace_id', $workspace->id)
+            ->update(['read_at' => now()]);
+
+        Cache::forget("user:{$request->user()->id}:workspace:{$workspace->id}:unread_notifications");
 
         return back();
     }