Refactor ActivityListItem to use function props for image caching

Replace @Emit decorator with function prop pattern for better parent control over image caching behavior. ActivityListItem now accepts onImageCache function prop that parent components can use to handle image caching with custom logic. Updated HomeView to use new function prop interface with simplified method signature.

src/views/HomeView.vue

@@ -227,9 +227,9 @@ Raymer * @version 1.0.0 */
             :is-registered="isRegistered"
             :active-did="activeDid"
             :confirmer-id-list="record.confirmerIdList"
+            :on-image-cache="cacheImageData"
             @load-claim="onClickLoadClaim"
             @view-image="openImageViewer"
-            @cache-image="cacheImageData"
             @confirm-claim="confirmClaim"
           />
         </ul>
@@ -1740,11 +1740,10 @@ export default class HomeView extends Vue {
    * Caches image data for sharing
    *
    * @public
-   * Called by ActivityListItem component
-   * @param event Event object
+   * Called by ActivityListItem component function prop
    * @param imageUrl URL of image to cache
    */
-  async cacheImageData(_event: Event, imageUrl: string) {
+  async cacheImageData(imageUrl: string) {
     try {
       // For images that might fail CORS, just store the URL
       // The Web Share API will handle sharing the URL appropriately