feat(scripts): add backfill for missing trend strategy snapshots

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

strategy_snapshot_lib.py

@@ -127,6 +127,7 @@ def save_trend_plan_snapshot(
     result_label: str,
     exit_price: float | None = None,
     pnl_amount: float | None = None,
+    closed_at: str | None = None,
 ) -> None:
     init_strategy_snapshot_table(conn)
     row = _row_dict(plan_row)
@@ -134,7 +135,7 @@ def save_trend_plan_snapshot(
     if plan_id <= 0:
         return
     m = cfg.get("app_module")
-    closed_at = (
+    close_ts = (closed_at or "").strip() or (
         m.app_now_str()
         if m is not None and hasattr(m, "app_now_str")
         else datetime.now(timezone.utc).strftime("%Y-%m-%d %H:%M:%S")
@@ -158,10 +159,10 @@ def save_trend_plan_snapshot(
             result_label,
             row.get("status"),
             row.get("opened_at"),
-            closed_at,
+            close_ts,
             pnl_amount,
             _json_dumps(payload),
-            closed_at,
+            close_ts,
         ),
     )
     prune_strategy_snapshots(conn, keep=STRATEGY_SNAPSHOTS_MAX_ROWS)