feat: 新增勘察派单功能及拜访详情页操作

新增客户空间拓扑API、勘察明细模型，重构勘察接口，新增拜访详情页操作逻辑及新建勘察派单页面

lib/features/customer/data/customer_api.dart

@@ -74,4 +74,12 @@ class CustomerApi {
             .map((e) => CustomerOption.fromJson((e as Map).cast<String, dynamic>()))
             .toList(),
       );
+
+  /// 客户空间拓扑：一次返回 建筑 → 楼层 → 房间（勘察明细取建筑/楼层/房间用）。
+  Future<ApiResponse<CustomerTopology>> topology(int customerId) =>
+      _client.get<CustomerTopology>(
+        '/customer-circuits/topology',
+        query: {'customerId': customerId},
+        parse: (d) => CustomerTopology.fromJson((d as Map).cast<String, dynamic>()),
+      );
 }

lib/features/customer/data/customer_models.dart

@@ -140,4 +140,86 @@ Color customerStatusBarColor(int status) => switch (status) {
   3 => AppColors.tertiaryContainer,
   4 => AppColors.statusError,
   _ => AppColors.borderRule,
-};
+};
+
+/// 客户空间拓扑（`/api/customer-circuits/topology`）：建筑 → 楼层 → 房间。
+class CustomerTopology {
+  const CustomerTopology({required this.buildings});
+
+  final List<CustomerTopologyBuilding> buildings;
+
+  factory CustomerTopology.fromJson(Map<String, dynamic> json) => CustomerTopology(
+    buildings: (json['buildings'] as List? ?? [])
+        .map((e) => CustomerTopologyBuilding.fromJson((e as Map).cast<String, dynamic>()))
+        .toList(),
+  );
+}
+
+class CustomerTopologyBuilding {
+  const CustomerTopologyBuilding({
+    required this.id,
+    required this.buildingName,
+    required this.floorCount,
+    required this.floorDownCount,
+    required this.floors,
+  });
+
+  final int id;
+  final String buildingName;
+
+  /// 地上楼层数（地上 1..N）。
+  final int floorCount;
+
+  /// 地下楼层数（地下 负1..负M）。
+  final int floorDownCount;
+  final List<CustomerTopologyFloor> floors;
+
+  factory CustomerTopologyBuilding.fromJson(Map<String, dynamic> json) =>
+      CustomerTopologyBuilding(
+        id: toIntOr(json['id'], 0),
+        buildingName: json['buildingName'] as String? ?? '',
+        floorCount: toIntOr(json['floorCount'], 0),
+        floorDownCount: toIntOr(json['floorDownCount'], 0),
+        floors: (json['floors'] as List? ?? [])
+            .map((e) => CustomerTopologyFloor.fromJson((e as Map).cast<String, dynamic>()))
+            .toList(),
+      );
+}
+
+class CustomerTopologyFloor {
+  const CustomerTopologyFloor({required this.floorNo, required this.rooms});
+
+  /// 楼层：正数为地上、负数为地下，如 `"1"` / `"-1"`。
+  final String floorNo;
+  final List<CustomerTopologyRoom> rooms;
+
+  factory CustomerTopologyFloor.fromJson(Map<String, dynamic> json) =>
+      CustomerTopologyFloor(
+        floorNo: json['floorNo'] == null ? '' : json['floorNo'].toString(),
+        rooms: (json['rooms'] as List? ?? [])
+            .map((e) => CustomerTopologyRoom.fromJson((e as Map).cast<String, dynamic>()))
+            .toList(),
+      );
+}
+
+class CustomerTopologyRoom {
+  const CustomerTopologyRoom({
+    required this.id,
+    required this.roomName,
+    required this.buildingId,
+    required this.floorNo,
+  });
+
+  final int id;
+  final String roomName;
+  final int buildingId;
+  final String floorNo;
+
+  factory CustomerTopologyRoom.fromJson(Map<String, dynamic> json) =>
+      CustomerTopologyRoom(
+        id: toIntOr(json['id'], 0),
+        roomName: json['roomName'] as String? ?? '',
+        buildingId: toIntOr(json['buildingId'], 0),
+        floorNo: json['floorNo'] == null ? '' : json['floorNo'].toString(),
+      );
+}