fix: whatsapp businessFriendList needs page+departmentId+type

Live validation: businessFriendList uses 'page' (not pageNum) and REQUIRES
departmentId (root) + type or returns empty. Same class of bug as wxUser/list.

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

yunke-server/tests/test_scrape_whatsapp_friends.py

@@ -130,7 +130,12 @@ async def test_scrape_whatsapp_friends_sends_pagination_body():
 
     client = _primed_client()
     try:
-        results = [r async for r in scrape_whatsapp_friends(client, page_size=1)]
+        results = [
+            r
+            async for r in scrape_whatsapp_friends(
+                client, department_id="ROOT_DEPT", page_size=1
+            )
+        ]
     finally:
         await client.aclose()
 
@@ -138,11 +143,14 @@ async def test_scrape_whatsapp_friends_sends_pagination_body():
     assert route.call_count == 2
 
     body1 = _json.loads(route.calls[0].request.content.decode())
-    assert body1["pageNum"] == 1
+    # businessFriendList uses `page` (not pageNum) + departmentId + type.
+    assert body1["page"] == 1
     assert body1["pageSize"] == 1
+    assert body1["departmentId"] == "ROOT_DEPT"
+    assert body1["type"] == "0"
 
     body2 = _json.loads(route.calls[1].request.content.decode())
-    assert body2["pageNum"] == 2
+    assert body2["page"] == 2
     assert body2["pageSize"] == 1