fix: 修复 Canvas 坐标转换问题

src/components/addDoc/seal.vue

@@ -341,11 +341,11 @@
           // 根据签章类型设置尺寸：公用章 120x120，个人章 120x40
           let width, height;
           if (data.sealType === 'private') {
-            width = 120;
-            height = 40;
+            width = 210;
+            height = 70;
           } else {
-            width = 120;
-            height = 120;
+            width = 200;
+            height = 200;
           }
 
           const posX = x - width / 2;