feat: grab sensor firmware version for detail sheet

lib/data/repositories/phoenix_sensor_repository.dart

@@ -52,6 +52,9 @@ class PhoenixSensorRepository implements SensorRepository {
   Future<Sensor> unplaceSensor(int id) async =>
       Sensor.fromJson(await client.unplaceSensor(id));
 
+  @override
+  Future<String?> getVersion(int id) => client.getVersion(id);
+
   @override
   Stream<Map<String, dynamic>> sensorEvents() => realtime
       .channelMessages('sensors')

lib/data/repositories/sensor_repository.dart

@@ -11,6 +11,8 @@ abstract class SensorRepository {
       {required int roomId, required double x, required double y});
   Future<Sensor> unplaceSensor(int id);
 
+  Future<String?> getVersion(int id);
+
   /// Stream of raw SensorsChannel messages. Each map contains an `event` key
   /// (`sensor_announced` or `sensor_enrollment_timeout`) plus the payload.
   Stream<Map<String, dynamic>> sensorEvents();