Add V16 broad EventChunk-SFT dataset card

README.md

@@ -40,8 +40,12 @@ game/research/formal/artifacts/v16_scales/sft_v16_scale100_mixture/
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 Their image references are repository-relative paths rooted at
-`game/research/formal/`. Download this repository preserving its directory
-layout so the `images` values resolve without rewriting.
+`game/research/formal/`. The complete release is stored under `archives/` as
+uncompressed tar shards plus `SHA256SUMS`, avoiding millions of separate Hub
+objects. Verify the checksums and extract every shard from the directory where
+the dataset checkout lives, for example: `for f in archives/*.tar; do tar -xf
+"$f"; done`. This recreates the original directory layout so the `images`
+values resolve without rewriting.
 
 ## Format