fix: test(browser): add Playwright test for app startup when initServerCapabilities() fails or times out (#9825)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

browser_tests/tests/serverCapabilities.spec.ts

@@ -0,0 +1,31 @@
+import { expect } from '@playwright/test'
+
+import { comfyPageFixture as test } from '../fixtures/ComfyPage'
+
+test.describe('Server Capabilities Resilience', { tag: '@slow' }, () => {
+  test('App starts successfully when /api/features returns 500', async ({
+    comfyPage
+  }) => {
+    await comfyPage.page.route('**/api/features**', async (route) => {
+      await route.fulfill({
+        status: 500,
+        contentType: 'application/json',
+        body: JSON.stringify({ error: 'Internal Server Error' })
+      })
+    })
+    await comfyPage.setup()
+
+    await expect(comfyPage.canvas).toBeVisible()
+  })
+
+  test('App starts successfully when /api/features network request fails', async ({
+    comfyPage
+  }) => {
+    await comfyPage.page.route('**/api/features**', async (route) => {
+      await route.abort('connectionrefused')
+    })
+    await comfyPage.setup()
+
+    await expect(comfyPage.canvas).toBeVisible()
+  })
+})