feat: 批量识别结果导出CSV

- 新增导出CSV文件功能，包含文本、判定结果、置信度、风险关键词
- 新增复制CSV内容到剪贴板功能
- CSV字段：文本、判定结果、置信度、垃圾概率、正常概率、风险关键词

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

miniprogram/pages/batch/index.js

@@ -79,5 +79,83 @@ Page({
       showCancel: false,
       confirmText: '关闭'
     })
+  },
+
+  generateCSV() {
+    const items = this.data.items
+    if (!items.length) return ''
+
+    const headers = ['文本', '判定结果', '置信度', '垃圾概率', '正常概率', '风险关键词']
+    const rows = items.map((item) => {
+      const prediction = item.prediction === 'spam' ? '垃圾信息' : '正常信息'
+      const confidence = item.confidence_text || '0%'
+      const spamProb = this.formatPercent(item.spam_probability, 4)
+      const hamProb = this.formatPercent(item.ham_probability, 4)
+      const tokens = (item.reason_tokens || []).map((t) => t.token || t).join('; ')
+      // CSV 转义：文本中的逗号和换行需要处理
+      const text = (item.text || '').replace(/"/g, '""')
+      const tokensEscaped = tokens.replace(/"/g, '""')
+      return `"${text}","${prediction}","${confidence}","${spamProb}","${hamProb}","${tokensEscaped}"`
+    })
+
+    return [headers.join(','), ...rows].join('\n')
+  },
+
+  exportCSV() {
+    const items = this.data.items
+    if (!items.length) {
+      wx.showToast({ title: '暂无识别结果可导出', icon: 'none' })
+      return
+    }
+
+    const csvContent = this.generateCSV()
+    const timestamp = new Date().toISOString().slice(0, 19).replace(/[T:]/g, '-')
+    const filename = `batch_detect_${timestamp}.csv`
+
+    // 写入临时文件
+    const fs = wx.getFileSystemManager()
+    const tempPath = `${wx.env.USER_DATA_PATH}/${filename}`
+
+    try {
+      fs.writeFileSync(tempPath, csvContent, 'utf8')
+      wx.showModal({
+        title: '导出成功',
+        content: `CSV文件已生成，是否打开查看？\n文件名：${filename}`,
+        confirmText: '打开',
+        cancelText: '关闭',
+        success: (res) => {
+          if (res.confirm) {
+            wx.openDocument({
+              filePath: tempPath,
+              fileType: 'csv',
+              showMenu: true,
+              fail: (err) => {
+                console.error('打开文件失败', err)
+                wx.showToast({ title: '打开失败，请检查文件管理器', icon: 'none' })
+              }
+            })
+          }
+        }
+      })
+    } catch (err) {
+      console.error('写入文件失败', err)
+      wx.showToast({ title: '导出失败', icon: 'none' })
+    }
+  },
+
+  copyCSVToClipboard() {
+    const items = this.data.items
+    if (!items.length) {
+      wx.showToast({ title: '暂无识别结果可复制', icon: 'none' })
+      return
+    }
+
+    const csvContent = this.generateCSV()
+    wx.setClipboardData({
+      data: csvContent,
+      success: () => {
+        wx.showToast({ title: 'CSV内容已复制到剪贴板', icon: 'success' })
+      }
+    })
   }
 })

miniprogram/pages/batch/index.wxml

@@ -56,6 +56,10 @@
 
   <view class="card fade-up fade-up-delay-3" wx:if="{{items.length}}">
     <view class="card-title">明细结果</view>
+    <view class="btn-row" style="margin-bottom: 12rpx;">
+      <button class="btn btn-ghost" bindtap="exportCSV">导出CSV文件</button>
+      <button class="btn btn-ghost" bindtap="copyCSVToClipboard">复制CSV内容</button>
+    </view>
     <view class="list-item" wx:for="{{items}}" wx:key="index">
       <view class="item-title">{{item.text}}</view>
       <view class="row">