Add action auto-scroll (#30057)

Adds an auto-scroll/follow feature to running actions (fix #25186, fix
#28535).

When new log lines are appended and the bottom of the logs container
(`.action-view-right`) is visible at this time, the page automatically
scrolls down to the bottom of the logs.

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Co-authored-by: silverwind <me@silverwind.io>
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>

web_src/js/components/ActionRunStatus.vue

@@ -7,8 +7,8 @@ import {SvgIcon} from '../svg.ts';
 
 withDefaults(defineProps<{
   status: 'success' | 'skipped' | 'waiting' | 'blocked' | 'running' | 'failure' | 'cancelled' | 'unknown',
-  size: number,
-  className: string,
+  size?: number,
+  className?: string,
   localeStatus?: string,
 }>(), {
   size: 16,