* refactor(sidebar-item): optimizate SiderbarItem.

* chore: update nested examples.

* fix: fix a wrong path.

* fix: fix a transition bug.

* fix: fix a wrong path.

* perf: using "router" mode of el-menu.

* Revert "perf: using "router" mode of el-menu."

This reverts commit cef02a30b02a31242521e9e678cfeaad6f09448c.

* fix: complement i18n text.