fix: 更新圖片 URL，將檔案格式從 .jpg 更改為 .png

Author: c-c-epr

src/eventRouter.ts

@@ -62,8 +62,8 @@ export async function eventRouter(event: any, channelAccessToken: string, ctx: E
               return [
                 {
                   type: "image",
-                  originalContentUrl: "https://lwt.ccepr.dev/original.jpg",
-                  previewImageUrl: "https://lwt.ccepr.dev/preview.jpg",
+                  originalContentUrl: "https://lwt.ccepr.dev/original.png",
+                  previewImageUrl: "https://lwt.ccepr.dev/preview.png",
                 },
               ];
             }