Add Pico alarm view model

tests/test_pico_core.py

@@ -583,3 +583,48 @@ def test_system_view_model():
     assert vm["wifi_api"] == "Available"
     assert vm["sensors"] == "3 / 4 OK"
     assert vm["ignition"] == "Off"
+
+
+def test_alarm_view_model_no_alarms():
+    from ui.alarm_view_model import AlarmViewModel
+
+    vm = AlarmViewModel([])
+
+    assert vm.count() == 0
+    assert vm.has_alarms() is False
+    assert vm.has_critical() is False
+    assert vm.should_buzz() is False
+    assert vm.primary_alarm() is None
+    assert vm.as_list() == []
+
+
+def test_alarm_view_model_critical_alarm():
+    from ui.alarm_view_model import AlarmViewModel
+
+    vm = AlarmViewModel(["fridge_zone_1_high"])
+
+    assert vm.count() == 1
+    assert vm.has_alarms() is True
+    assert vm.has_critical() is True
+    assert vm.should_buzz() is True
+
+    primary = vm.primary_alarm()
+
+    assert primary["severity"] == "critical"
+    assert primary["title"] == "Fridge Zone 1 High Temp"
+
+
+def test_alarm_view_model_sensor_failure():
+    from ui.alarm_view_model import AlarmViewModel
+
+    vm = AlarmViewModel(["sensor_failure:outside"])
+
+    assert vm.has_alarms() is True
+    assert vm.has_critical() is False
+    assert vm.should_buzz() is False
+
+    alarm = vm.primary_alarm()
+
+    assert alarm["severity"] == "warning"
+    assert alarm["title"] == "Sensor Failure"
+    assert alarm["detail"] == "Outside"