fix: debug 分享卡片生成问题

src/utils/share.ts

@@ -106,6 +106,12 @@ const drawLabel = (ctx: any, x: number, y: number, width: number, height: number
     ctx.restore()
 }
 
+/** 给图片 URL 加随机参数，避免同一链接二次加载不触发 onload */
+function with_cache_bust(url: string): string {
+    const sep = url.includes('?') ? '&' : '?';
+    return `${url}${sep}_t=${Date.now()}_${Math.random().toString(36).slice(2)}`;
+}
+
 // 工具函数 - OffscreenCanvas 下加载图片（使用 offscreen.createImage）
 const loadImage = (src: string): Promise<any> => {
     return new Promise((resolve, reject) => {
@@ -117,7 +123,7 @@ const loadImage = (src: string): Promise<any> => {
             const img = off.createImage()
             img.onload = () => resolve(img)
             img.onerror = reject
-            img.src = src
+            img.src = with_cache_bust(src)
         } catch (e) {
             reject(e)
         }