feat: 添加 njson.MarshalSafe 方法，同时修复之前的MarshalStrSafe方法

njson/json.go

@@ -23,10 +23,23 @@ func MarshalStr(v any) (string, error) {
 	return string(data), nil
 }
 
+// MarshalSafe marshals v into json bytes.
+// return an empty byte slice if an error occurred.
+func MarshalSafe(v any) []byte {
+	ret, err := Marshal(v)
+	if err != nil {
+		return []byte{}
+	}
+	return ret
+}
+
 // MarshalStrSafe marshals v into a string.
 // return an empty string if an error occurred.
 func MarshalStrSafe(v any) string {
-	ret, _ := MarshalStr(v)
+	ret, err := MarshalStr(v)
+	if err != nil {
+		return ""
+	}
 	return ret
 }