feat(n8n-runner): support async response handling (#2487)

* feat(n8n-runner): support async response handling

* fix(n8n-runner): expose response handling in form

* fix(n8n-runner): preserve async response semantics

---------

Co-authored-by: dadachann <185672915+dadachann@users.noreply.github.com>

web/tests/unit/n8n-auth-field-visibility.test.mjs

@@ -0,0 +1,52 @@
+import assert from 'node:assert/strict';
+import fs from 'node:fs';
+import path from 'node:path';
+import test from 'node:test';
+import ts from 'typescript';
+import { fileURLToPath } from 'node:url';
+
+const currentDirectory = path.dirname(fileURLToPath(import.meta.url));
+const sourcePath = path.resolve(
+  currentDirectory,
+  '../../src/app/home/components/dynamic-form/N8nAuthFieldVisibility.ts',
+);
+
+function loadVisibilityPolicy() {
+  const source = fs.readFileSync(sourcePath, 'utf8');
+  const compiled = ts.transpileModule(source, {
+    compilerOptions: { module: ts.ModuleKind.CommonJS },
+  }).outputText;
+  const loadedModule = { exports: {} };
+  new Function('require', 'module', 'exports', compiled)(
+    () => {
+      throw new Error('N8nAuthFieldVisibility must not have runtime imports');
+    },
+    loadedModule,
+    loadedModule.exports,
+  );
+  return loadedModule.exports;
+}
+
+test('shows response handling with the other common n8n fields', () => {
+  const { shouldShowN8nConfigField } = loadVisibilityPolicy();
+
+  for (const field of [
+    'webhook-url',
+    'auth-type',
+    'timeout',
+    'output-key',
+    'response-handling',
+  ]) {
+    assert.equal(shouldShowN8nConfigField(field, 'none'), true, field);
+  }
+});
+
+test('shows only fields for the selected n8n authentication method', () => {
+  const { shouldShowN8nConfigField } = loadVisibilityPolicy();
+
+  assert.equal(shouldShowN8nConfigField('basic-username', 'basic'), true);
+  assert.equal(shouldShowN8nConfigField('basic-password', 'jwt'), false);
+  assert.equal(shouldShowN8nConfigField('jwt-secret', 'jwt'), true);
+  assert.equal(shouldShowN8nConfigField('header-name', 'header'), true);
+  assert.equal(shouldShowN8nConfigField('unrelated-field', 'none'), false);
+});