feat: 新增常量设置

src/main/java/com/fanruan/constants/Constants.java

@@ -0,0 +1,6 @@
+package com.fanruan.constants;
+import com.fr.stable.EncodeConstants;
+
+public class Constants {
+    public static final String ENCODING_UTF_8 = EncodeConstants.ENCODING_UTF_8;
+}