fix: font stack, sparklines, and DA1 response issues

- Restore terminal.options.fontFamily assignment for proper font stack handling
- Add dynamic service registration to DockerStatsCollector for docker watch mode
- Remove force_redraw on reconnect that caused DA1 responses to display as text

tests/test_docker_stats.py

@@ -168,6 +168,35 @@ class TestDockerStatsCollector:
 
         assert len(collector._cpu_history["test"]) == STATS_HISTORY_SIZE
 
+    def test_add_service_dynamic(self):
+        """Services can be added dynamically after start."""
+        collector = DockerStatsCollector("/nonexistent")
+        collector._service_names = ["svc1"]
+        
+        collector.add_service("svc2")
+        assert "svc2" in collector._service_names
+        
+        # Adding same service again is a no-op
+        collector.add_service("svc2")
+        assert collector._service_names.count("svc2") == 1
+
+    def test_remove_service_dynamic(self):
+        """Services can be removed dynamically."""
+        from collections import deque
+        
+        collector = DockerStatsCollector("/nonexistent")
+        collector._service_names = ["svc1", "svc2"]
+        collector._cpu_history["svc1"] = deque([10.0, 20.0])
+        collector._prev_cpu["svc1"] = (100, 200)
+        
+        collector.remove_service("svc1")
+        assert "svc1" not in collector._service_names
+        assert "svc1" not in collector._cpu_history
+        assert "svc1" not in collector._prev_cpu
+        
+        # Removing non-existent service is safe
+        collector.remove_service("nonexistent")  # Should not raise
+
 
 class TestLocalServerSparklineEndpoint:
     """Tests for the CPU sparkline endpoint in LocalServer."""

tests/test_local_server_websocket_integration.py

@@ -81,19 +81,12 @@ async def test_websocket_creates_session_on_resize(tmp_path):
         await client.close()
 
     assert created["args"] == ("test", 90, 25)
-    # Reconnect should trigger redraw without creating a new session
-    called = {"redraw": 0, "stdin": 0}
+    # Reconnect to an existing session should reuse it and send replay buffer
 
     class DummySession:
         def is_running(self):
             return True
 
-        async def force_redraw(self):
-            called["redraw"] += 1
-
-        async def send_bytes(self, data: bytes):
-            called["stdin"] += 1
-
     server.session_manager.routes["test"] = "sid"
     server.session_manager.sessions["sid"] = DummySession()
 
@@ -111,9 +104,6 @@ async def test_websocket_creates_session_on_resize(tmp_path):
     finally:
         await client.close()
 
-    assert called["redraw"] == 1
-    assert called["stdin"] == 1
-
 
 @pytest.mark.asyncio
 async def test_websocket_ping_pong(tmp_path):