refactor(transfer): 移除发起转让页的售价字段 — 线下柜台签合同交易

APP 端树转让仅完成系统层面的所有权变更 + 算力调整（撤回旧用户算力、
新增至新用户及其团队），价格由用户线下到柜台签署合同确定。

变更详情：
- transfer_initiate_page.dart:
  · 移除 _priceController、_feeRate、费用相关 getter
  · 移除"每棵售价"输入框和费用计算卡片 UI
  · 移除 _feeRow 辅助方法
  · 更新说明文案：强调线下柜台签合同
  · 更新确认弹窗：仅显示买方账号和转让棵数
  · API 调用改用 treeCount 替代 pricePerTree
- transfer_service.dart:
  · createTransfer() 参数从 pricePerTree(double) 改为 treeCount(int)
  · 请求体字段同步调整

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

frontend/mobile-app/lib/core/services/transfer_service.dart

@@ -236,21 +236,21 @@ class TransferService {
   /// 发起转让
   ///
   /// [buyerAccountSequence] 买方账号
-  /// [plantingOrderNos] 要转让的认种订单号列表
-  /// [pricePerTree] 每棵售价
+  /// [plantingOrderNos] 要转让的认种订单号列表（空列表时由后端自动选择）
+  /// [treeCount] 转让棵数
   Future<TransferOrder> createTransfer({
     required String buyerAccountSequence,
     required List<String> plantingOrderNos,
-    required double pricePerTree,
+    required int treeCount,
   }) async {
     try {
-      debugPrint('[TransferService] 发起转让: buyer=$buyerAccountSequence, trees=${plantingOrderNos.length}');
+      debugPrint('[TransferService] 发起转让: buyer=$buyerAccountSequence, treeCount=$treeCount');
       final response = await _apiClient.post(
         '/transfers',
         data: {
           'buyerAccountSequence': buyerAccountSequence,
           'plantingOrderNos': plantingOrderNos,
-          'pricePerTree': pricePerTree.toString(),
+          'treeCount': treeCount,
         },
       );
 

frontend/mobile-app/lib/features/transfer/presentation/pages/transfer_initiate_page.dart

@@ -11,9 +11,9 @@ import '../../../../routes/route_paths.dart';
 //
 // 用户发起树转让的表单页面：
 // - 输入买方账号
-// - 输入每棵售价
-// - 自动计算手续费（5%）和卖方到账金额
+// - 输入转让棵数
 // - 确认发起转让
+// 注：价格线下柜台签合同交易，APP 仅完成系统层面所有权 + 算力转移
 //
 // === 回滚方式 ===
 // 删除 features/transfer/ 目录
@@ -28,27 +28,18 @@ class TransferInitiatePage extends ConsumerStatefulWidget {
 
 class _TransferInitiatePageState extends ConsumerState<TransferInitiatePage> {
   final _buyerController = TextEditingController();
-  final _priceController = TextEditingController();
   final _treeCountController = TextEditingController(text: '1');
   bool _isSubmitting = false;
   String? _errorMessage;
 
-  // 平台手续费率
-  static const double _feeRate = 0.05;
-
   @override
   void dispose() {
     _buyerController.dispose();
-    _priceController.dispose();
     _treeCountController.dispose();
     super.dispose();
   }
 
-  double get _pricePerTree => double.tryParse(_priceController.text) ?? 0;
   int get _treeCount => int.tryParse(_treeCountController.text) ?? 1;
-  double get _totalPrice => _pricePerTree * _treeCount;
-  double get _feeAmount => _totalPrice * _feeRate;
-  double get _sellerReceive => _totalPrice - _feeAmount;
 
   Future<void> _handleSubmit() async {
     final buyer = _buyerController.text.trim();
@@ -56,10 +47,6 @@ class _TransferInitiatePageState extends ConsumerState<TransferInitiatePage> {
       setState(() => _errorMessage = '请输入买方账号');
       return;
     }
-    if (_pricePerTree <= 0) {
-      setState(() => _errorMessage = '请输入有效的每棵售价');
-      return;
-    }
     if (_treeCount <= 0) {
       setState(() => _errorMessage = '请输入有效的转让棵数');
       return;
@@ -77,12 +64,9 @@ class _TransferInitiatePageState extends ConsumerState<TransferInitiatePage> {
         ),
         content: Text(
           '买方账号: $buyer\n'
-          '转让棵数: $_treeCount 棵\n'
-          '每棵售价: ${_pricePerTree.toStringAsFixed(0)} USDT\n'
-          '总价: ${_totalPrice.toStringAsFixed(0)} USDT\n'
-          '手续费: ${_feeAmount.toStringAsFixed(2)} USDT (${(_feeRate * 100).toStringAsFixed(0)}%)\n'
-          '您将收到: ${_sellerReceive.toStringAsFixed(2)} USDT\n\n'
-          '转让发起后需要卖方确认，确认后 Saga 流程将自动执行。',
+          '转让棵数: $_treeCount 棵\n\n'
+          '确认后系统将完成树所有权变更及算力调整。\n'
+          '交易价格请线下柜台签署合同确定。',
           style: const TextStyle(color: Color(0xFF5D4037), fontSize: 14, height: 1.6),
         ),
         actions: [
@@ -115,7 +99,7 @@ class _TransferInitiatePageState extends ConsumerState<TransferInitiatePage> {
       final order = await service.createTransfer(
         buyerAccountSequence: buyer,
         plantingOrderNos: [], // 由后端根据棵数自动选择
-        pricePerTree: _pricePerTree,
+        treeCount: _treeCount,
       );
 
       if (mounted) {
@@ -178,7 +162,7 @@ class _TransferInitiatePageState extends ConsumerState<TransferInitiatePage> {
                             SizedBox(width: 8),
                             Expanded(
                               child: Text(
-                                '转让已认种的果树所有权。发起后需卖方确认，系统将自动完成资金冻结、所有权变更、算力调整等流程。',
+                                '转让已认种的果树所有权。系统将自动完成所有权变更及算力调整，交易价格请线下柜台签署合同确定。',
                                 style: TextStyle(fontSize: 13, color: Color(0xFF8B5A2B)),
                               ),
                             ),
@@ -207,48 +191,8 @@ class _TransferInitiatePageState extends ConsumerState<TransferInitiatePage> {
                         inputFormatters: [FilteringTextInputFormatter.digitsOnly],
                         onChanged: (_) => setState(() {}),
                       ),
-                      const SizedBox(height: 20),
-
-                      // 每棵售价
-                      _buildLabel('每棵售价 (USDT)'),
-                      const SizedBox(height: 8),
-                      _buildTextField(
-                        controller: _priceController,
-                        hintText: '输入每棵售价',
-                        keyboardType: const TextInputType.numberWithOptions(decimal: true),
-                        inputFormatters: [FilteringTextInputFormatter.allow(RegExp(r'[\d.]'))],
-                        onChanged: (_) => setState(() {}),
-                      ),
                       const SizedBox(height: 24),
 
-                      // 费用计算卡片
-                      if (_pricePerTree > 0) ...[
-                        Container(
-                          padding: const EdgeInsets.all(16),
-                          decoration: BoxDecoration(
-                            color: const Color(0x99FFFFFF),
-                            borderRadius: BorderRadius.circular(12),
-                            boxShadow: const [
-                              BoxShadow(
-                                color: Color(0x1A000000),
-                                blurRadius: 6,
-                                offset: Offset(0, 4),
-                              ),
-                            ],
-                          ),
-                          child: Column(
-                            children: [
-                              _feeRow('总价', '${_totalPrice.toStringAsFixed(0)} USDT'),
-                              _feeRow('手续费 (${(_feeRate * 100).toStringAsFixed(0)}%)', '${_feeAmount.toStringAsFixed(2)} USDT'),
-                              const Divider(color: Color(0xFFEAE0C8)),
-                              _feeRow('您将收到', '${_sellerReceive.toStringAsFixed(2)} USDT',
-                                  valueColor: const Color(0xFFD4AF37)),
-                            ],
-                          ),
-                        ),
-                        const SizedBox(height: 24),
-                      ],
-
                       // 错误信息
                       if (_errorMessage != null) ...[
                         Container(
@@ -429,24 +373,4 @@ class _TransferInitiatePageState extends ConsumerState<TransferInitiatePage> {
     );
   }
 
-  Widget _feeRow(String label, String value, {Color? valueColor}) {
-    return Padding(
-      padding: const EdgeInsets.symmetric(vertical: 4),
-      child: Row(
-        mainAxisAlignment: MainAxisAlignment.spaceBetween,
-        children: [
-          Text(label, style: const TextStyle(fontSize: 13, color: Color(0xFF745D43))),
-          Text(
-            value,
-            style: TextStyle(
-              fontSize: 14,
-              fontWeight: FontWeight.w500,
-              color: valueColor ?? const Color(0xFF5D4037),
-              fontFamily: 'Inter',
-            ),
-          ),
-        ],
-      ),
-    );
-  }
 }