feat: add realtime GNSS monitor with telemetry websocket

backend/tests/mqtt/test_mixed_parser.py

@@ -25,3 +25,24 @@ def test_parse_mixed_payload_returns_rtcm_summary() -> None:
 
     event_types = {event["event_type"] for event in events}
     assert "rtcm_summary" in event_types
+
+
+def test_parse_nmea_sentences_extracts_satellite_details_and_used_ids() -> None:
+    payload = (
+        b"$GPGSA,A,3,02,05,12,,,,,,,,,,1.50,0.90,1.20*00\r\n"
+        b"$GPGSV,1,1,04,02,17,213,40,05,29,121,37,12,66,314,44,25,14,048,39*71\r\n"
+    )
+
+    events = parse_nmea_sentences(payload)
+    gsa_event = next(event for event in events if event["event_type"] == "nmea_gsa")
+    gsv_event = next(event for event in events if event["event_type"] == "nmea_gsv")
+
+    assert gsa_event["payload"]["used_satellite_ids"] == ["02", "05", "12"]
+    assert gsv_event["payload"]["constellation"] == "GPS"
+    assert len(gsv_event["payload"]["satellites"]) == 4
+    assert gsv_event["payload"]["satellites"][0] == {
+        "satellite_id": "02",
+        "elevation_deg": 17,
+        "azimuth_deg": 213,
+        "snr_dbhz": 40,
+    }