fix(ui): align GitLab App create modal with GitHub

Match the GitHub create modal layout: intro copy, name/group row,
system-wide warning, self-hosted accordion (URL/API/SSH), and a
bottom Continue button instead of a duplicate header Save.

tests/Feature/GitlabSourceCreateModalTest.php

@@ -0,0 +1,50 @@
+<?php
+
+use App\Livewire\Source\Gitlab\Create;
+use App\Models\GitlabApp;
+use App\Models\Team;
+use App\Models\User;
+use Illuminate\Foundation\Testing\RefreshDatabase;
+use Livewire\Livewire;
+
+uses(RefreshDatabase::class);
+
+beforeEach(function () {
+    $this->team = Team::factory()->create();
+    $this->user = User::factory()->create();
+    $this->team->members()->attach($this->user->id, ['role' => 'owner']);
+
+    $this->actingAs($this->user);
+    session(['currentTeam' => $this->team]);
+});
+
+describe('GitLab source create modal', function () {
+    test('matches github create modal structure', function () {
+        Livewire::test(Create::class)
+            ->assertSee('This is required if you would like to get full integration')
+            ->assertSee('Self-hosted GitLab')
+            ->assertSee('Continue')
+            ->assertDontSee('>Save</', false)
+            ->assertDontSeeHtml('<h2>New GitLab App</h2>');
+    });
+
+    test('creates a gitlab app with defaults for gitlab.com', function () {
+        Livewire::test(Create::class)
+            ->set('name', 'my-gitlab')
+            ->call('createGitLabApp')
+            ->assertRedirect();
+
+        $app = GitlabApp::where('name', 'my-gitlab')->first();
+        expect($app)->not->toBeNull()
+            ->and($app->html_url)->toBe('https://gitlab.com')
+            ->and($app->api_url)->toBe('https://gitlab.com/api/v4')
+            ->and($app->custom_user)->toBe('git')
+            ->and($app->custom_port)->toBe(22);
+    });
+
+    test('derives api url when html url changes', function () {
+        Livewire::test(Create::class)
+            ->set('html_url', 'https://gitlab.example.com')
+            ->assertSet('api_url', 'https://gitlab.example.com/api/v4');
+    });
+});