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_ntfy_integration.py

@@ -8,11 +8,11 @@ import urllib.request
 
 
 class TestNtfyTopics:
-    def test_cc_topic_exists_and_writable(self):
-        """Verify C&C topic exists and accepts messages."""
-        from engine.config import NTFY_CC_TOPIC
+    def test_cc_cmd_topic_exists_and_writable(self):
+        """Verify C&C CMD topic exists and accepts messages."""
+        from engine.config import NTFY_CC_CMD_TOPIC
 
-        topic_url = NTFY_CC_TOPIC.replace("/json", "")
+        topic_url = NTFY_CC_CMD_TOPIC.replace("/json", "")
         test_message = f"test_{int(time.time())}"
 
         req = urllib.request.Request(
@@ -29,7 +29,30 @@ class TestNtfyTopics:
             with urllib.request.urlopen(req, timeout=10) as resp:
                 assert resp.status == 200
         except Exception as e:
-            raise AssertionError(f"Failed to write to C&C topic: {e}") from e
+            raise AssertionError(f"Failed to write to C&C CMD topic: {e}") from e
+
+    def test_cc_resp_topic_exists_and_writable(self):
+        """Verify C&C RESP topic exists and accepts messages."""
+        from engine.config import NTFY_CC_RESP_TOPIC
+
+        topic_url = NTFY_CC_RESP_TOPIC.replace("/json", "")
+        test_message = f"test_{int(time.time())}"
+
+        req = urllib.request.Request(
+            topic_url,
+            data=test_message.encode("utf-8"),
+            headers={
+                "User-Agent": "mainline-test/0.1",
+                "Content-Type": "text/plain",
+            },
+            method="POST",
+        )
+
+        try:
+            with urllib.request.urlopen(req, timeout=10) as resp:
+                assert resp.status == 200
+        except Exception as e:
+            raise AssertionError(f"Failed to write to C&C RESP topic: {e}") from e
 
     def test_message_topic_exists_and_writable(self):
         """Verify message topic exists and accepts messages."""
@@ -54,12 +77,12 @@ class TestNtfyTopics:
         except Exception as e:
             raise AssertionError(f"Failed to write to message topic: {e}") from e
 
-    def test_cc_topic_readable(self):
-        """Verify we can read messages from C&C topic."""
-        from engine.config import NTFY_CC_TOPIC
+    def test_cc_cmd_topic_readable(self):
+        """Verify we can read messages from C&C CMD topic."""
+        from engine.config import NTFY_CC_CMD_TOPIC
 
         test_message = f"integration_test_{int(time.time())}"
-        topic_url = NTFY_CC_TOPIC.replace("/json", "")
+        topic_url = NTFY_CC_CMD_TOPIC.replace("/json", "")
 
         req = urllib.request.Request(
             topic_url,
@@ -74,11 +97,11 @@ class TestNtfyTopics:
         try:
             urllib.request.urlopen(req, timeout=10)
         except Exception as e:
-            raise AssertionError(f"Failed to write to C&C topic: {e}") from e
+            raise AssertionError(f"Failed to write to C&C CMD topic: {e}") from e
 
         time.sleep(1)
 
-        poll_url = f"{NTFY_CC_TOPIC}?poll=1&limit=1"
+        poll_url = f"{NTFY_CC_CMD_TOPIC}?poll=1&limit=1"
         req = urllib.request.Request(
             poll_url,
             headers={"User-Agent": "mainline-test/0.1"},
@@ -91,11 +114,14 @@ class TestNtfyTopics:
                     data = json.loads(body.split("\n")[0])
                     assert isinstance(data, dict)
         except Exception as e:
-            raise AssertionError(f"Failed to read from C&C topic: {e}") from e
+            raise AssertionError(f"Failed to read from C&C CMD topic: {e}") from e
 
     def test_topics_are_different(self):
-        """Verify C&C and message topics are different."""
-        from engine.config import NTFY_CC_TOPIC, NTFY_TOPIC
+        """Verify C&C CMD/RESP and message topics are different."""
+        from engine.config import NTFY_CC_CMD_TOPIC, NTFY_CC_RESP_TOPIC, NTFY_TOPIC
 
-        assert NTFY_CC_TOPIC != NTFY_TOPIC
-        assert "_cc" in NTFY_CC_TOPIC
+        assert NTFY_CC_CMD_TOPIC != NTFY_TOPIC
+        assert NTFY_CC_RESP_TOPIC != NTFY_TOPIC
+        assert NTFY_CC_CMD_TOPIC != NTFY_CC_RESP_TOPIC
+        assert "_cc_cmd" in NTFY_CC_CMD_TOPIC
+        assert "_cc_resp" in NTFY_CC_RESP_TOPIC