Add shard_00012.manifest.json

manifests/shard_00012.manifest.json

@@ -0,0 +1,19 @@
+{
+  "shard_id": 12,
+  "rows": 119858,
+  "size_mb": 200.21,
+  "compression": "zstd",
+  "source_breakdown": {
+    "cosmopedia_v2": 0.0851,
+    "arithmetic": 0.1186,
+    "tiny_math": 0.1187,
+    "fineweb_edu": 0.1689,
+    "finewiki": 0.3384,
+    "python_edu": 0.1017,
+    "tiny_textbooks": 0.0237,
+    "mini_en": 0.0177,
+    "tiny_strange": 0.0272
+  },
+  "created_at": "2026-07-13T15:45:27.652628Z",
+  "run_name": "bison-data-v2"
+}