Update README.md with 98 models from MWC leaderboard

README.md

@@ -40,10 +40,7 @@ Core columns:
 - `average` — Mean of available benchmark scores
 - `benchmarks_completed` — Number of benchmarks with scores
 
-Per-benchmark columns (for each benchmark):
-
-- `<benchmark>_score` — Accuracy score (0-1 scale)
-- `<benchmark>_stderr` — Standard error
+One column per benchmark — each cell contains `[score, stderr]` as a JSON tuple, or empty if not evaluated:
 
 Benchmarks: