fix(test): update test for empty default title

tests/test_app.py

@@ -1942,11 +1942,11 @@ def test_login_page_shows_expired_banner(client):
 
 
 def test_create_page_defaults_to_untitled(client):
-    """Creating a page with empty title defaults to 'Untitled'."""
+    """Creating a page with empty title defaults to empty string (CSS placeholder shows 'New page')."""
     resp = client.post("/board/api/pages?title=&section=Private", follow_redirects=False)
     assert resp.status_code == 200
     data = resp.json()
-    assert data["title"] == "Untitled"
+    assert data["title"] == ""
 
 
 def test_styled_404_page(client):