feat: complete Epic 0 — foundation migration & infrastructure setup

Stories 0.2-0.5: rename folders→declarations (backend+frontend), configure
Redis for cache/queue/sessions, add foundation database migrations
(permissions, archived_at), replace DeclarationStatus enum with architecture
lifecycle values, create DeclarationObserver for status transition validation
and auto-archive, fix controller status transitions to respect observer rules.

93 tests pass (240 assertions).

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

app/Notifications/DeclarationMentionNotification.php

@@ -2,19 +2,19 @@
 
 namespace App\Notifications;
 
-use App\Models\Folder;
+use App\Models\Declaration;
 use App\Models\User;
 use Illuminate\Bus\Queueable;
 use Illuminate\Contracts\Queue\ShouldQueue;
 use Illuminate\Notifications\Messages\MailMessage;
 use Illuminate\Notifications\Notification;
 
-class FolderMentionNotification extends Notification implements ShouldQueue
+class DeclarationMentionNotification extends Notification implements ShouldQueue
 {
     use Queueable;
 
     public function __construct(
-        public Folder $folder,
+        public Declaration $declaration,
         public User $mentionedBy,
         public string $message,
     ) {}
@@ -33,24 +33,24 @@ class FolderMentionNotification extends Notification implements ShouldQueue
     public function toDatabase(object $notifiable): array
     {
         return [
-            'folder_id' => $this->folder->id,
-            'folder_title' => $this->folder->title,
+            'declaration_id' => $this->declaration->id,
+            'declaration_title' => $this->declaration->title,
             'mentioned_by_id' => $this->mentionedBy->id,
             'mentioned_by_name' => $this->mentionedBy->name,
             'message' => $this->message,
-            'url' => route('folders.show', $this->folder),
+            'url' => route('declarations.show', $this->declaration),
         ];
     }
 
     public function toMail(object $notifiable): MailMessage
     {
         return (new MailMessage)
-            ->subject('Vous avez été mentionné - '.$this->folder->title)
-            ->markdown('emails.folder-mention', [
-                'folderTitle' => $this->folder->title,
+            ->subject('Vous avez été mentionné - '.$this->declaration->title)
+            ->markdown('emails.declaration-mention', [
+                'declarationTitle' => $this->declaration->title,
                 'mentionedByName' => $this->mentionedBy->name,
                 'message' => $this->message,
-                'url' => route('folders.show', $this->folder),
+                'url' => route('declarations.show', $this->declaration),
             ]);
     }
 }