Initial commit: OAuth IAM Laravel application

Laravel-based OAuth/IAM service with Passport, Vue 3 frontend, and
Docker Compose setup for local and production deployment.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

lang/en/messages.php

@@ -0,0 +1,13 @@
+<?php
+
+return [
+    'invalid_credentials' => 'Invalid credentials.',
+    'account_deactivated' => 'This account is deactivated.',
+    'account_pending_approval' => 'Your account is pending approval by an administrator.',
+    'registration_pending' => 'Account created. An administrator has to approve it before you can sign in.',
+    'cannot_remove_own_admin_role' => "You can't remove your own admin role.",
+    'cannot_delete_self' => "You can't delete your own account.",
+    'cannot_delete_last_admin' => "You can't delete the last administrator.",
+    'self_service_requires_user' => 'This resource is self-service: it needs a token with an associated user (does not work with client_credentials).',
+    'user_not_trashed' => 'This user is not in the trash.',
+];