feat: add MQTT topic parsing and pipeline config

backend/tests/mqtt/test_topic.py

@@ -0,0 +1,12 @@
+import pytest
+
+from app.mqtt.topic import extract_device_id
+
+
+def test_extract_device_id_success() -> None:
+    assert extract_device_id("terminal/device-001/raw") == "device-001"
+
+
+def test_extract_device_id_rejects_invalid_topic() -> None:
+    with pytest.raises(ValueError, match="terminal/\\{device_id\\}/raw"):
+        extract_device_id("terminal/device-001/nmea")