fix: 显示下发智能体的云端图标

tests/e2e/teacher-preview-layout.spec.ts

@@ -70,6 +70,26 @@ async function geometry(page: Page) {
   });
 }
 
+test('distributed icons load over HTTP and broken images fall back in the titlebar', async ({ page }) => {
+  await page.route('https://yuxi.example.test/api/storage/public/images/agent-0.png', route => route.fulfill({
+    contentType: 'image/svg+xml',
+    body: '<svg xmlns="http://www.w3.org/2000/svg" width="32" height="32"><circle cx="16" cy="16" r="15" fill="blue"/></svg>',
+  }));
+  await page.route('https://yuxi.example.test/api/storage/public/images/agent-1.png', route => route.fulfill({ status: 404 }));
+  await page.goto(`${baseUrl}?agents=2&icons=1`);
+  const custom = page.getByRole('button', { name: '与智能体1聊天' }).locator('img');
+  const fallback = page.getByRole('button', { name: '与智能体2聊天' }).locator('img');
+  const speaker = page.getByRole('button', { name: '打开这条智能体消息' }).locator('img');
+  await expect(custom).toHaveAttribute('src', 'https://yuxi.example.test/api/storage/public/images/agent-0.png');
+  await expect(custom).toHaveCSS('image-rendering', 'auto');
+  await expect(speaker).toHaveAttribute('src', 'https://yuxi.example.test/api/storage/public/images/agent-0.png');
+  await expect(fallback).toHaveAttribute('src', /avatar-06\.png/);
+  for (const img of [custom, fallback, speaker]) {
+    await expect.poll(() => img.evaluate(node => (node as HTMLImageElement).naturalWidth)).toBeGreaterThan(0);
+  }
+  await page.screenshot({ path: test.info().outputPath('distributed-icons.png') });
+});
+
 for (const size of [{ width: 1440, height: 900 }, { width: 1180, height: 720 }, { width: 1000, height: 640 }]) {
   test(`preview only clears overlapping speech at ${size.width}x${size.height}`, async ({ page }) => {
     await page.setViewportSize(size);