feat(security): add session timeout + transaction wrapping (B1)

Session timeout: configurable idle (default 30min) and absolute (default 8h)
timeouts via DB settings, enforced in web/index.php on every request.
Timestamps set at login in action layer; graceful fallback for pre-existing
sessions.

Transaction wrapping: UserAccountService.createFromAdmin/register, roles
create/edit, and permissions edit now wrap multi-step DB operations in
transactions to guarantee atomicity.

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

tests/Service/User/UserAccountServiceTest.php

@@ -2,6 +2,7 @@
 
 namespace MintyPHP\Tests\Service\User;
 
+use MintyPHP\Repository\Support\DatabaseSessionRepository;
 use MintyPHP\Repository\User\UserListQueryRepositoryInterface;
 use MintyPHP\Repository\User\UserReadRepositoryInterface;
 use MintyPHP\Repository\User\UserWriteRepositoryInterface;
@@ -418,7 +419,8 @@ class UserAccountServiceTest extends TestCase
         ?UserSettingsGateway $settingsGateway = null,
         ?UserScopeGateway $scopeGateway = null,
         ?UserDirectoryGateway $directoryGateway = null,
-        ?SystemAuditService $auditService = null
+        ?SystemAuditService $auditService = null,
+        ?DatabaseSessionRepository $databaseSessionRepository = null
     ): UserAccountService {
         $readRepository = $readRepository ?? $this->createMock(UserReadRepositoryInterface::class);
         $writeRepository = $writeRepository ?? $this->createMock(UserWriteRepositoryInterface::class);
@@ -463,6 +465,7 @@ class UserAccountServiceTest extends TestCase
         }
 
         $auditService = $auditService ?? $this->createMock(SystemAuditService::class);
+        $databaseSessionRepository = $databaseSessionRepository ?? $this->createMock(DatabaseSessionRepository::class);
 
         return new UserAccountService(
             $readRepository,
@@ -473,7 +476,8 @@ class UserAccountServiceTest extends TestCase
             $settingsGateway,
             $scopeGateway,
             $directoryGateway,
-            $auditService
+            $auditService,
+            $databaseSessionRepository
         );
     }
 }