Remove top-level v1/v2 after moving to legacy/

v1/v1_direct/splits/split_config_v1.json

@@ -1,32 +0,0 @@
-{
-  "version": "v1",
-  "seed": 20260318,
-  "experiment_wallets_file": "wallet_ids_diverse_nonoverlap_2000_seed20260318.txt",
-  "experiment_wallets": 2000,
-  "split_ratios": {
-    "train": 0.7,
-    "validation": 0.15,
-    "test": 0.15
-  },
-  "time_order_keys": [
-    "stance_first_block",
-    "stance_last_block",
-    "market_id"
-  ],
-  "history_mode": "rolling within split construction",
-  "prompt_history_max_items": 30,
-  "counts": {
-    "train": {
-      "samples": 98094,
-      "wallets": 2000
-    },
-    "validation": {
-      "samples": 21147,
-      "wallets": 2000
-    },
-    "test": {
-      "samples": 22204,
-      "wallets": 2000
-    }
-  }
-}