try to fix streaming responses

tests/test_dashboard.py

@@ -33,6 +33,21 @@ def test_dashboard_served_with_all_panels():
         tracker.stop()
 
 
+def test_dashboard_chat_uses_streaming_fetch():
+    tracker = TrackerServer(billing=BillingLedger())
+    port = tracker.start()
+    try:
+        html = urllib.request.urlopen(
+            f"http://127.0.0.1:{port}/dashboard"
+        ).read().decode()
+    finally:
+        tracker.stop()
+
+    assert "stream: true" in html
+    assert ".body.getReader()" in html
+    assert 'data === "[DONE]"' in html
+
+
 def test_dashboard_served_by_follower():
     """A tracker that is not the leader (unreachable peers → never elected)
     still serves the dashboard from its own replicated state."""