[branch-2.1][fix](metadata)Add FE metadata-related file checks #40546 (#41113)

## Proposed changes

#40546

fe/fe-common/src/main/java/org/apache/doris/common/Config.java

@@ -2806,4 +2806,8 @@ public class Config extends ConfigBase {
     @ConfField(mutable = true, description = {"表示最大锁持有时间，超过该时间会打印告警日志，单位秒",
             "Maximum lock hold time; logs a warning if exceeded"})
     public static long  max_lock_hold_threshold_seconds = 10;
+
+    @ConfField(mutable = true, description = {"元数据同步是否开启安全模式",
+            "Is metadata synchronization enabled in safe mode"})
+    public static boolean meta_helper_security_mode = false;
 }