Update README.md

Added Time Split details

README.md

@@ -24,3 +24,11 @@ This dataset contains only clips **longer than 15 seconds** from:
 
 ## Filtering
 Kept clips where duration > 15s (computed on the fly via streaming).
+
+## --- Split: train ---
+15-30s   count=40840  total_sec=864899.59  total_min=14414.99  total_hrs=240.25
+>30s     count=315  total_sec=10316.36  total_min=171.94  total_hrs=2.87
+
+## --- Split: validation ---
+15-30s   count=4654  total_sec=98955.82  total_min=1649.26  total_hrs=27.49
+>30s     count=42  total_sec=1387.42  total_min=23.12  total_hrs=0.39