feat(service): warn when required environment variables are missing

Surface unset required service env vars in the configuration checker
popup and sidebar, refresh on env updates, and keep the env table
horizontally scrollable with correct managed/hardcoded pagination order.

tests/Feature/EnvironmentVariableSearchTest.php

@@ -211,6 +211,48 @@ it('searches service environment variables without requiring preview variables',
         ->and($component->instance()->showPreview)->toBeFalse();
 });
 
+it('pins required service environment variables only while their values are missing', function () {
+    $service = Service::factory()->create([
+        'environment_id' => $this->environment->id,
+        'docker_compose_raw' => <<<'YAML'
+services:
+  app:
+    image: nginx
+    environment:
+      HARDCODED_FIRST: configured
+YAML,
+    ]);
+
+    EnvironmentVariable::create([
+        'key' => 'OPTIONAL_FIRST',
+        'value' => 'configured',
+        'order' => 1,
+        'resourceable_type' => Service::class,
+        'resourceable_id' => $service->id,
+    ]);
+
+    $required = EnvironmentVariable::create([
+        'key' => 'REQUIRED_SECOND',
+        'value' => '',
+        'order' => 2,
+        'is_required' => true,
+        'resourceable_type' => Service::class,
+        'resourceable_id' => $service->id,
+    ]);
+
+    $component = Livewire::test(All::class, ['resource' => $service])
+        ->call('loadEnvironmentVariables');
+
+    expect($component->instance()->environmentVariablePageRows->pluck('environmentVariable.key')->all())
+        ->toBe(['REQUIRED_SECOND', 'OPTIONAL_FIRST', 'HARDCODED_FIRST']);
+
+    $required->update(['value' => 'configured']);
+    $component->call('$refresh');
+
+    expect($component->instance()->environmentVariablePageRows->pluck('environmentVariable.key')->all())
+        ->toBe(['OPTIONAL_FIRST', 'REQUIRED_SECOND', 'HARDCODED_FIRST']);
+});
+
 it('does not show the empty production message when search only matches hardcoded variables', function () {
     $service = Service::factory()->create([
         'environment_id' => $this->environment->id,