fix(options): expose chain DTE in env UI and show nearest expiries for OO

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

lib/options/options_register.py

@@ -364,11 +364,13 @@ def register_options_routes(app: Flask, cfg: dict[str, Any]) -> None:
         if ex is None:
             return jsonify({"ok": False, "msg": err})
         u = (request.args.get("underlying") or cfg["default_underly"]).upper()
+        # 热更新:链展示天数每次读 env,保存后刷新链即可
+        chain_max_dte = _env_float("OKX_OPTIONS_CHAIN_MAX_DTE_DAYS", float(cfg.get("chain_max_dte_days") or 14))
         try:
             chain = cfg["build_option_chain"](
                 ex,
                 u,
-                max_dte_days=cfg["chain_max_dte_days"],
+                max_dte_days=chain_max_dte,
                 itm_only=False,
                 itm_max_dist_usd=cfg["itm_max_dist"],
             )
@@ -385,7 +387,7 @@ def register_options_routes(app: Flask, cfg: dict[str, Any]) -> None:
                     "ok": False,
                     "msg": chain_err or "暂无到期日,请稍后点「刷新链」",
                     **chain,
-                    "chain_max_dte_days": cfg["chain_max_dte_days"],
+                    "chain_max_dte_days": chain_max_dte,
                     "ask_liq_filter_enabled": ask_liq_filter,
                     "budget_buffer": budget_buffer,
                     "trade_budget": cfg["trade_budget"],
@@ -395,7 +397,7 @@ def register_options_routes(app: Flask, cfg: dict[str, Any]) -> None:
             {
                 "ok": True,
                 **chain,
-                "chain_max_dte_days": cfg["chain_max_dte_days"],
+                "chain_max_dte_days": chain_max_dte,
                 "ask_liq_filter_enabled": ask_liq_filter,
                 "budget_buffer": budget_buffer,
                 "trade_budget": cfg["trade_budget"],