fix(工具箱/二维码解析和生成): 优化界面样式，解决图片显示超出的问题

src/views/ToolboxView/Conversion/QrcodeReaderAndGenerator.vue

@@ -307,6 +307,8 @@ function handleSelectQrImage(options) {
 
     .n-image {
       margin: auto;
+      width: 100%;
+      height: 100%;
     }
   }
 
@@ -336,6 +338,8 @@ function handleSelectQrImage(options) {
 
     .n-image {
       margin: auto;
+      width: 100%;
+      height: 100%;
       image-rendering: pixelated;
     }
   }