fix: Sensor schema drift with upstream API

lib/data/repositories/phoenix_sensor_repository.dart

@@ -24,10 +24,9 @@ class PhoenixSensorRepository implements SensorRepository {
       Sensor.fromJson(await client.getSensor(id));
 
   @override
-  Future<Sensor> updateSensor(int id, {String? name, double? rssiRef}) async {
+  Future<Sensor> updateSensor(int id, {String? name}) async {
     final params = <String, dynamic>{};
     if (name != null) params['name'] = name;
-    if (rssiRef != null) params['rssi_ref'] = rssiRef;
     return Sensor.fromJson(await client.updateSensor(id, params));
   }
 

lib/data/repositories/sensor_repository.dart

@@ -4,7 +4,7 @@ abstract class SensorRepository {
   Future<List<Sensor>> getSensors();
   Future<List<Sensor>> getUnplacedSensors();
   Future<Sensor> getSensor(int id);
-  Future<Sensor> updateSensor(int id, {String? name, double? rssiRef});
+  Future<Sensor> updateSensor(int id, {String? name});
   Future<void> deleteSensor(int id);
   Future<Sensor> placeSensor(int id,
       {required int roomId, required double x, required double y});

lib/domain/models/sensor.dart

@@ -6,16 +6,14 @@ class Sensor {
     this.roomId,
     this.x,
     this.y,
-    this.rssiRef,
   });
 
   final int id;
   final String sensorId; // BLE MAC / provisioning device ID
   final String? name;    // human-readable label
   final int? roomId;
-  final double? x;       // floor_x from API
-  final double? y;       // floor_y from API
-  final double? rssiRef;
+  final double? x;       // room relative
+  final double? y;       // room relative
 
   bool get isPlaced => roomId != null;
   String get displayName => name ?? sensorId;
@@ -25,9 +23,8 @@ class Sensor {
         sensorId: json['sensor_id'] as String,
         name: json['name'] as String?,
         roomId: json['room_id'] as int?,
-        x: (json['floor_x'] as num?)?.toDouble(),
-        y: (json['floor_y'] as num?)?.toDouble(),
-        rssiRef: (json['rssi_ref'] as num?)?.toDouble(),
+        x: (json['x'] as num?)?.toDouble(),
+        y: (json['y'] as num?)?.toDouble(),
       );
 
   Sensor copyWith({
@@ -44,6 +41,5 @@ class Sensor {
         roomId: roomId ?? this.roomId,
         x: x ?? this.x,
         y: y ?? this.y,
-        rssiRef: rssiRef ?? this.rssiRef,
       );
 }

lib/features/sensors/sensor_detail_screen.dart

@@ -49,11 +49,6 @@ class _Body extends ConsumerWidget {
         crossAxisAlignment: CrossAxisAlignment.stretch,
         children: [
           _InfoRow(label: 'Device ID', value: sensor.sensorId),
-          if (sensor.rssiRef != null)
-            _InfoRow(
-              label: 'RSSI reference',
-              value: '${sensor.rssiRef!.toStringAsFixed(1)} dBm',
-            ),
           _InfoRow(
             label: 'Floor position',
             value: sensor.isPlaced