[Developer] #618 add structured data browser

src/main/java/com/cloudhandson/vpdbackoffice/domain/structured/StructuredDataPreview.java

@@ -0,0 +1,12 @@
+package com.cloudhandson.vpdbackoffice.domain.structured;
+
+import java.util.List;
+import java.util.Map;
+
+public record StructuredDataPreview(
+    StructuredDataTable table,
+    List<String> columns,
+    List<Map<String, Object>> rows,
+    int rowLimit
+) {
+}