Add metadata for batch 28

batch_28_metadata.json

@@ -0,0 +1,7 @@
+{
+  "upload_time": "2025-06-23T08:03:05.070795",
+  "total_trees": 284,
+  "new_trees": 8,
+  "batch_number": 28,
+  "upload_interval": 30
+}