feat: self-hosted GitLab Apps OAuth integration

Adds self-hosted GitLab OAuth sources so Coolify can connect to a self-managed GitLab instance, list private repositories, clone over an OAuth token, and deploy (the GitLab counterpart to GitHub Apps).

Hardening: authenticated, one-time team-bound OAuth callback state; token redaction in deploy logs; custom host port/path kept in clone and ls-remote URLs; submodule OAuth auth; system-wide source selection. Covered by unit and feature tests.

cosigned by OpenAI Codex at M1 Max

app/Livewire/Project/New/Select.php

@@ -170,6 +170,12 @@ class Select extends Component
                 'description' => 'You can deploy public & private repositories through your GitHub Apps.',
                 'logo' => asset('svgs/github.svg'),
             ],
+            [
+                'id' => 'private-gitlab-app',
+                'name' => 'Private Repository (with GitLab App)',
+                'description' => 'You can deploy public & private repositories through your GitLab Apps.',
+                'logo' => asset('svgs/gitlab.svg'),
+            ],
             [
                 'id' => 'private-deploy-key',
                 'name' => 'Private Repository (with Deploy Key)',