Add Pico communication timeout tracking

tests/test_pico_core.py

@@ -350,3 +350,79 @@ def test_communication_service_http_fallback_relay():
     assert state.relays["fridge"] is True
     assert fake_uart.writes == []
     assert fake_requests.urls == ["http://192.168.4.1/relay/fridge/on"]
+
+
+def test_communication_service_marks_uart_connected_on_status():
+    from comms.uart_client import UartClient
+    from comms.communication_service import CommunicationService
+
+    fake = FakeUart()
+    fake.read_chunks = [
+        b'{"type":"status_response","timestamp":1,"network":{"uart_connected":true}}\n'
+    ]
+
+    state = AppState()
+    current_time = [100.0]
+
+    service = CommunicationService(
+        UartClient(fake),
+        state,
+        clock=lambda: current_time[0],
+        timeout_seconds=5,
+    )
+
+    service.poll()
+
+    assert state.network["uart_connected"] is True
+    assert service.last_status_received_at == 100.0
+
+
+def test_communication_service_marks_uart_disconnected_after_timeout():
+    from comms.uart_client import UartClient
+    from comms.communication_service import CommunicationService
+
+    fake = FakeUart()
+    fake.read_chunks = [
+        b'{"type":"status_response","timestamp":1,"network":{"uart_connected":true}}\n'
+    ]
+
+    state = AppState()
+    current_time = [100.0]
+
+    service = CommunicationService(
+        UartClient(fake),
+        state,
+        clock=lambda: current_time[0],
+        timeout_seconds=5,
+    )
+
+    service.poll()
+    assert state.network["uart_connected"] is True
+
+    current_time[0] = 106.0
+    service.poll()
+
+    assert state.network["uart_connected"] is False
+
+
+def test_communication_service_auto_selects_http_fallback_when_uart_down():
+    from comms.uart_client import UartClient
+    from comms.http_client import HttpClient
+    from comms.communication_service import CommunicationService
+
+    fake_uart = FakeUart()
+    fake_requests = FakeRequests()
+
+    state = AppState()
+    service = CommunicationService(
+        UartClient(fake_uart),
+        state,
+        HttpClient(fake_requests),
+        clock=lambda: 100.0,
+        timeout_seconds=5,
+    )
+
+    service.poll()
+
+    assert service.auto_select_transport() is True
+    assert service.use_http_fallback is True