增加仪表板统计数据的导出功能

frontend/src/components/StatsDashboard.css

@@ -693,10 +693,43 @@
   grid-column: 1 / -1;
 }
 
-.stats-card h3 {
+.stats-card-header {
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  gap: 12px;
   margin-bottom: 0.75rem;
 }
 
+.stats-card-header h3 {
+  margin: 0;
+}
+
+.stats-export-btn {
+  padding: 6px 12px;
+  background: #607D8B;
+  color: white;
+  border: none;
+  border-radius: 4px;
+  cursor: pointer;
+  font-size: 13px;
+  font-weight: 600;
+  white-space: nowrap;
+}
+
+.stats-export-btn:hover:not(:disabled) {
+  background: #546E7A;
+}
+
+.stats-export-btn:disabled {
+  opacity: 0.6;
+  cursor: not-allowed;
+}
+
+.stats-card h4 {
+  margin-top: 0;
+}
+
 .stats-card h4 {
   font-size: 0.95rem;
   color: #555;

frontend/src/components/StatsDashboard.jsx

@@ -327,6 +327,34 @@ const StatsDashboard = () => {
     URL.revokeObjectURL(url)
   }
 
+  const handleExportTradeStats = () => {
+    if (!tradeStats) {
+      alert('暂无交易统计数据可导出')
+      return
+    }
+    const timestamp = new Date().toISOString().slice(0, 19).replace(/:/g, '-')
+    const filename = `交易统计_最近${tradeStats.days || 7}天_${timestamp}.json`
+    const exportData = {
+      exported_at: new Date().toISOString(),
+      days: tradeStats.days,
+      by_symbol: tradeStats.by_symbol || [],
+      hourly_agg: tradeStats.hourly_agg || [],
+      suggestions: tradeStats.suggestions || { blacklist: [], whitelist: [] },
+      daily: tradeStats.daily || [],
+      by_hour: tradeStats.by_hour || [],
+    }
+    const dataStr = JSON.stringify(exportData, null, 2)
+    const dataBlob = new Blob([dataStr], { type: 'application/json' })
+    const url = URL.createObjectURL(dataBlob)
+    const link = document.createElement('a')
+    link.href = url
+    link.download = filename
+    document.body.appendChild(link)
+    link.click()
+    document.body.removeChild(link)
+    URL.revokeObjectURL(url)
+  }
+
   return (
     <div className="dashboard">
       <div style={{ display: 'flex', justifyContent: 'space-between', alignItems: 'center', marginBottom: '20px' }}>
@@ -851,7 +879,18 @@ const StatsDashboard = () => {
 
         {/* 交易统计（最近 7 天）：按交易对净盈亏/胜率、按小时净盈亏、白名单/黑名单建议 */}
         <div className="dashboard-card stats-card">
+          <div className="stats-card-header">
             <h3>交易统计（最近 7 天）</h3>
+            <button
+              type="button"
+              onClick={handleExportTradeStats}
+              disabled={!tradeStats}
+              className="stats-export-btn"
+              title="导出交易统计为 JSON，便于离线分析"
+            >
+              导出 JSON
+            </button>
+          </div>
           {tradeStats ? (
             <>
               <div className="stats-section">