!760 fix(bpm):缺少了subString 方法，应该是商城功能改subString这个工具类，不小心影响了bpm的功能

Merge pull request !760 from 徐煜东/fix-bpm-20250405

Author: YunaiV

src/utils/index.ts

@@ -536,3 +536,18 @@ export const sliceName = (name: string, start: number, end: number) => {
   }
   return name
 }
+
+/**
+ * 截取字符串
+ *
+ * @param str 字符串
+ * @param start 开始位置
+ * @param end 结束位置
+ */
+
+export const subString = (str: string, start: number, end: number) => {
+  if (str.length > end) {
+    return str.slice(start, end)
+  }
+  return str
+}