fix: 修复 Chrome 90 智能体文档上传失败

- 复用兼容 UUID 生成逻辑，移除对 crypto.randomUUID 的依赖

- 补充旧浏览器缺失 randomUUID 时的上传回归测试

easyflow-ui-admin/app/src/components/ai-chat/useChatDocumentUploads.test.ts

@@ -16,6 +16,7 @@ vi.mock('./mediaApi', () => mediaApi);
 describe('useChatDocumentUploads', () => {
   afterEach(() => {
     vi.restoreAllMocks();
+    vi.unstubAllGlobals();
     Object.values(mediaApi).forEach((mock) => mock.mockReset());
   });
 
@@ -68,6 +69,44 @@ describe('useChatDocumentUploads', () => {
     );
   });
 
+  it('uses getRandomValues when randomUUID is unavailable', async () => {
+    const getRandomValues = vi.fn((values: Uint8Array) => {
+      values.fill(171);
+      return values;
+    });
+    vi.stubGlobal('crypto', { getRandomValues });
+    mediaApi.uploadAgentChatDocument.mockImplementation(
+      async (file, _context, uploadId) => ({
+        data: {
+          attachmentRef: 'document:chrome-90',
+          mimeType: file.type,
+          name: file.name,
+          size: file.size,
+          status: 'READY',
+          uploadId,
+        },
+        errorCode: 0,
+      }),
+    );
+
+    const uploads = useChatDocumentUploads();
+    await uploads.addFiles(
+      [new File(['document'], 'chrome-90.pdf', { type: 'application/pdf' })],
+      { agentId: 'agent-1', mode: 'FORMAL', sessionId: 'session-1' },
+    );
+
+    expect(getRandomValues).toHaveBeenCalled();
+    expect(mediaApi.uploadAgentChatDocument).toHaveBeenCalledWith(
+      expect.any(File),
+      { agentId: 'agent-1', mode: 'FORMAL', sessionId: 'session-1' },
+      expect.stringMatching(/^[a-f0-9]{32}$/),
+    );
+    expect(uploads.items.value[0]).toMatchObject({
+      status: 'ready',
+      uploadId: expect.stringMatching(/^[a-f0-9]{32}$/),
+    });
+  });
+
   it('exposes a server read failure without continuing to poll', async () => {
     mediaApi.uploadAgentChatDocument.mockResolvedValue({
       data: {