style(ops): 上月趋势线改回虚线并降低透明度

线条、圆点、面积填充整体降低 opacity，作为当月数据的淡色参考线。

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

apps/web-antd/src/views/ops/cleaning/work-order/dashboard/index.vue

@@ -248,8 +248,9 @@ function getTrendChartOptions(): ECOption {
         smooth: true,
         symbol: 'circle',
         symbolSize: 6,
+        lineStyle: { type: 'dashed', opacity: 0.6 },
         areaStyle: {
-          opacity: 0.1,
+          opacity: 0.06,
           color: {
             type: 'linear', x: 0, y: 0, x2: 0, y2: 1,
             colorStops: [
@@ -260,7 +261,7 @@ function getTrendChartOptions(): ECOption {
         },
         emphasis: { focus: 'series' },
         data: monthly.lastMonth.createdData,
-        itemStyle: { color: '#52c41a' },
+        itemStyle: { color: '#52c41a', opacity: 0.6 },
       },
     ],
   };