Issue #128 Fix JsonPathAstBacked method visibility

Co-authored-by: simbo1905 <simbo1905@60hertz.com>

Author: cursoragent

json-java21-jsonpath/src/main/java/json/java21/jsonpath/JsonPathAstPath.java

@@ -32,7 +32,7 @@ public String toString() {
     }
 
     @Override
-    JsonPathAst.Root ast() {
+    public JsonPathAst.Root ast() {
         return ast;
     }
 }