feat(daemon): add daemon mode with C&C and display abstraction

- Add display abstraction with swappable backends (TerminalDisplay, NullDisplay)
- Separate C&C into RX/TX topics for serial-like communication
- Add StreamController with automatic ntfy topic warmup
- Add performance monitoring for render + display stages
- Update AGENTS.md and README.md with daemon/cmd operating procedures
- Add clean/clobber tasks to mise.toml
- Add tests for display, effects controller, and controller warmup
- Fix bug where /effects reorder command was unreachable

tests/test_controller.py

@@ -83,3 +83,35 @@ class TestStreamControllerCleanup:
         controller.cleanup()
 
         mock_mic_instance.stop.assert_called_once()
+
+
+class TestStreamControllerWarmup:
+    """Tests for StreamController topic warmup."""
+
+    def test_warmup_topics_idempotent(self):
+        """warmup_topics can be called multiple times."""
+        StreamController._topics_warmed = False
+
+        with patch("urllib.request.urlopen") as mock_urlopen:
+            StreamController.warmup_topics()
+            StreamController.warmup_topics()
+
+            assert mock_urlopen.call_count >= 3
+
+    def test_warmup_topics_sets_flag(self):
+        """warmup_topics sets the warmed flag."""
+        StreamController._topics_warmed = False
+
+        with patch("urllib.request.urlopen"):
+            StreamController.warmup_topics()
+
+            assert StreamController._topics_warmed is True
+
+    def test_warmup_topics_skips_after_first(self):
+        """warmup_topics skips after first call."""
+        StreamController._topics_warmed = True
+
+        with patch("urllib.request.urlopen") as mock_urlopen:
+            StreamController.warmup_topics()
+
+            mock_urlopen.assert_not_called()