docs: supply documents for pager.hugContent of discrete legend

docs/assets/option/en/component/legend-discrete.md

@@ -834,6 +834,10 @@ Default current page number.
 
 The spacing of the page turner from the same legend.
 
+#### hugContent(boolean) = false
+
+Whether the pager hugs the legend content. Defaults to `false`, where the pager is pinned to the far end of the legend's available space, the items and the pager are justified to opposite ends, and the legend bounds always occupy the full available space. When enabled, the pager is placed right after the last legend item (using `space` as the gap, falling back to the end-pinned position when the content fills the available space), and the paging clip region shrinks to the actual content extent, so the bounds of "items + pager" hug the content. This makes it easy to center the whole block for legends with `orient` set to `'top'` | `'bottom'`.
+
 #### animation(boolean) = true
 
 Whether to turn on animation.

docs/assets/option/zh/component/legend-discrete.md

@@ -821,6 +821,10 @@ value: {
 
 翻页器同图例的间距。
 
+#### hugContent(boolean) = false
+
+是否让翻页器紧贴图例内容排布。默认为 `false`，翻页器固定在图例可用空间的末端，图例项与翻页器呈两端对齐，且图例包围盒始终占满可用空间。开启后翻页器紧跟最后一个图例项（间距为 `space`，图例内容占满可用空间时退化为末端对齐），同时分页裁剪区域收缩到图例内容的实际尺寸，使「图例项 + 翻页器」的包围盒随内容自适应，便于配合 `orient` 为 `'top'` | `'bottom'` 的图例将整块内容居中放置。
+
 #### animation(boolean) = true
 
 是否开启动画。