fix(security) : add role checks on Gitea API resources and all MCP tools

- GiteaBranch, GiteaBranchName, GiteaPullRequest: require ROLE_USER
- All 22 MCP tools: require ROLE_USER (ROLE_ADMIN for users/clients listing)

Tickets: T-002, T-007

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

src/Mcp/Tool/TaskMeta/ListGroupsTool.php

@@ -7,16 +7,23 @@ namespace App\Mcp\Tool\TaskMeta;
 use App\Mcp\Tool\Serializer;
 use App\Repository\TaskGroupRepository;
 use Mcp\Capability\Attribute\McpTool;
+use Symfony\Bundle\SecurityBundle\Security;
+use Symfony\Component\Security\Core\Exception\AccessDeniedException;
 
 #[McpTool(name: 'list-groups', description: 'List task groups, optionally filtered by project. Groups are per-project (each group belongs to one project).')]
 class ListGroupsTool
 {
     public function __construct(
         private readonly TaskGroupRepository $taskGroupRepository,
+        private readonly Security $security,
     ) {}
 
     public function __invoke(?int $projectId = null, bool $archived = false): string
     {
+        if (!$this->security->isGranted('ROLE_USER')) {
+            throw new AccessDeniedException('Access denied: ROLE_USER required.');
+        }
+
         $criteria = ['archived' => $archived];
         if (null !== $projectId) {
             $criteria['project'] = $projectId;