Prevent duplicate strategy trade snapshots on plan close.

Finalize plans before writing snapshots, dedupe on startup and page load, and add a cleanup script for existing repeated rows.

Co-authored-by: Cursor <cursoragent@cursor.com>

scripts/dedupe_strategy_snapshots.py

@@ -0,0 +1,67 @@
+#!/usr/bin/env python3
+"""清理 strategy_trade_snapshots 重复行（同计划 + 同结果仅保留 id 最大的一条）。
+
+用法（在实例目录，如 crypto_monitor_gate_bot）：
+  python ../scripts/dedupe_strategy_snapshots.py
+  python ../scripts/dedupe_strategy_snapshots.py --db crypto.db
+"""
+from __future__ import annotations
+
+import argparse
+import os
+import sqlite3
+import sys
+from pathlib import Path
+
+ROOT = Path(__file__).resolve().parents[1]
+sys.path.insert(0, str(ROOT))
+
+from strategy_snapshot_lib import dedupe_strategy_snapshots, init_strategy_snapshot_table  # noqa: E402
+
+
+def main() -> int:
+    parser = argparse.ArgumentParser(description="Dedupe strategy_trade_snapshots rows.")
+    parser.add_argument(
+        "--db",
+        default=os.getenv("DB_PATH", "crypto.db"),
+        help="SQLite database path (default: DB_PATH or crypto.db)",
+    )
+    parser.add_argument("--dry-run", action="store_true", help="Count only, do not delete")
+    args = parser.parse_args()
+
+    db_path = Path(args.db)
+    if not db_path.is_file():
+        print(f"DB not found: {db_path}", file=sys.stderr)
+        return 1
+
+    conn = sqlite3.connect(str(db_path))
+    conn.row_factory = sqlite3.Row
+    init_strategy_snapshot_table(conn)
+    before = conn.execute("SELECT COUNT(*) AS c FROM strategy_trade_snapshots").fetchone()["c"]
+    dup_groups = conn.execute(
+        """SELECT strategy_type, source_id, result_label, COUNT(*) AS n
+           FROM strategy_trade_snapshots
+           GROUP BY strategy_type, source_id, result_label
+           HAVING n > 1
+           ORDER BY n DESC"""
+    ).fetchall()
+    extra = sum(int(r["n"]) - 1 for r in dup_groups)
+    print(f"snapshots total={before}, duplicate rows to remove={extra}, groups={len(dup_groups)}")
+    for r in dup_groups[:20]:
+        print(
+            f"  {r['strategy_type']} plan={r['source_id']} "
+            f"{r['result_label']} x{r['n']}"
+        )
+    if args.dry_run:
+        conn.close()
+        return 0
+    removed = dedupe_strategy_snapshots(conn)
+    conn.commit()
+    after = conn.execute("SELECT COUNT(*) AS c FROM strategy_trade_snapshots").fetchone()["c"]
+    conn.close()
+    print(f"removed={removed}, remaining={after}")
+    return 0
+
+
+if __name__ == "__main__":
+    raise SystemExit(main())