fix: 卖出时输入框改用disabled禁止编辑，点击自动展开持仓列表

pages/detail/detail.vue

@@ -164,9 +164,16 @@
               v-model="transactionForm.stockCode" 
               class="form-input" 
               :placeholder="transactionType === 'sell' ? '请选择要卖出的持仓' : '请输入股票代码'"
-              :readonly="transactionType === 'sell'"
+              :disabled="transactionType === 'sell'"
               @input="transactionType === 'buy' ? searchStock(e.detail.value) : () => {}"
-              @click="transactionType === 'sell' && searchResults.length > 0 ? () => {} : () => {}"
+              @click="transactionType === 'sell' ? (searchResults.length = positions.value.map(pos => ({
+                ticker: pos.stockCode,
+                stockName: pos.stockName,
+                assetType: pos.assetType || 'Stock',
+                currency: pos.currency,
+                amount: pos.amount,
+                exchange: ''
+              }))) : () => {}"
             />
             <!-- 搜索下拉列表/持仓列表 -->
             <view class="search-dropdown" v-if="searchResults.length > 0">