feat(components): [image] fix #8919 bug (#8920)

Co-authored-by: wanyiding <wanyiding@tuhu.cn>

packages/components/image/src/image.ts

@@ -63,5 +63,6 @@ export const imageEmits = {
   error: (evt: Event) => evt instanceof Event,
   switch: (val: number) => isNumber(val),
   close: () => true,
+  show: () => true,
 }
 export type ImageEmits = typeof imageEmits

packages/components/image/src/image.vue

@@ -207,6 +207,7 @@ function clickHandler() {
   prevOverflow = document.body.style.overflow
   document.body.style.overflow = 'hidden'
   showViewer.value = true
+  emit('show')
 }
 
 function closeViewer() {