fix(backtest): 结果页4个显示bug—成交枚举/时间/浮点精度/日志空

1. 交易详情方向/开平显原始枚举: Direction.LONG/Offset.OPEN → 买/卖、开仓/平仓/平今/平昨
   (TradesTable 加 fmtDir/fmtOff, 方向带涨跌色)
2. 交易详情时间 2024-06-25T00:00:00+08:00 → 2024-06-25 (日内带时分则保留)
3. 每日收益浮点精度 0.6533000000054017 → 0.65 (toFixed2, 涨跌色), 日期去 00:00:00
4. 日志tab硬编码"暂无日志数据": 前端接 getLog(/task/:id/log) + 后端 cta_engine 加
   stdout tee 把引擎 load/run/stats 输出落盘到 {task_id}.log (worker 进程内隔离)
   → 新回测日志 tab 显示真实引擎输出(2117字)

验证: 交易 买/开仓/2024-06-25, 收益 0.15, 日志 2117字真实内容

frontend/src/views/backtest/Result.vue

@@ -3,7 +3,7 @@ import { ref, computed, onMounted } from 'vue'
 import { useRoute } from 'vue-router'
 import {
   getResult, getEquityCurve, getDailyPnl, getTrades, getKline,
-  getRelativeMetrics, getBenchmarkCurve, getRiskSeries,
+  getRelativeMetrics, getBenchmarkCurve, getRiskSeries, getLog,
   type EquityPoint, type PnlPoint, type Trade, type KlineBar,
   type RelativeMetrics, type BenchmarkCurveData, type RiskSeriesData,
 } from '@/api/backtest'
@@ -42,6 +42,7 @@ const equity = ref<EquityPoint[]>([])
 const pnl = ref<PnlPoint[]>([])
 const trades = ref<Trade[]>([])
 const kline = ref<KlineBar[]>([])
+const logText = ref('')
 
 // statEntries is no longer used in the new layout but kept for potential future use
 // const statEntries = computed(() =>
@@ -135,10 +136,32 @@ onMounted(async () => {
         kline.value = []
       }
     }
+    try {
+      logText.value = await getLog(taskId)
+    } catch {
+      logText.value = ''
+    }
   } finally {
     loading.value = false
   }
 })
+
+// 每日收益格式化：浮点精度 → 2 位；日期去 00:00:00
+function fmtPnl(v: number | string): string {
+  const n = typeof v === 'number' ? v : parseFloat(v)
+  if (!Number.isFinite(n)) return String(v)
+  return n.toFixed(2)
+}
+function fmtPnlClass(v: number | string): string {
+  const n = typeof v === 'number' ? v : parseFloat(v)
+  if (!Number.isFinite(n) || n === 0) return ''
+  return n > 0 ? 'up' : 'down'
+}
+function fmtDate(d: string): string {
+  if (!d) return ''
+  const s = String(d).slice(0, 19).replace('T', ' ')
+  return s.endsWith(' 00:00:00') ? s.slice(0, 10) : s
+}
 </script>
 
 <template>
@@ -219,8 +242,12 @@ onMounted(async () => {
           <template #header><span class="section-title">每日收益</span></template>
           <div class="daily-pnl-section">
             <el-table :data="pnl" stripe size="small" empty-text="无数据">
-              <el-table-column prop="date" label="日期" width="120" />
-              <el-table-column prop="pnl" label="收益" width="120" />
+              <el-table-column label="日期" width="140">
+                <template #default="{ row }"><span class="mono">{{ fmtDate(row.date) }}</span></template>
+              </el-table-column>
+              <el-table-column label="收益" width="120" align="right">
+                <template #default="{ row }"><span class="mono" :class="fmtPnlClass(row.pnl)">{{ fmtPnl(row.pnl) }}</span></template>
+              </el-table-column>
             </el-table>
           </div>
         </el-card>
@@ -230,7 +257,7 @@ onMounted(async () => {
       <el-tab-pane label="日志输出">
         <el-card>
           <template #header><span class="section-title">系统日志</span></template>
-          <pre class="log-output">暂无日志数据</pre>
+          <pre class="log-output">{{ logText || '暂无日志数据' }}</pre>
         </el-card>
       </el-tab-pane>
     </el-tabs>