env 锁定币本位并清掉对冲/USDC 配置项。

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

lib/options/options_margin_mode_lib.py

@@ -24,22 +24,14 @@ def _env_float(name: str, default: float) -> float:
 
 
 def normalize_options_margin_mode(raw: Any = None) -> str:
-    """返回 usdc | coin;未配置时默认币本位."""
-    if raw is None:
-        raw = os.getenv("OKX_OPTIONS_MARGIN_MODE")
-    v = str(raw or MODE_COIN).strip().lower()
-    if v in ("usdc", "usdc_margin", "usd_margin", "u本位", "u"):
-        return MODE_USDC
-    if v in ("coin", "coin_margin", "crypto", "crypto_margin", "币本位"):
-        return MODE_COIN
-    # 空串或未知值:默认币本位
-    if not v:
-        return MODE_COIN
+    """币本位专用机:始终 coin;历史 usdc 配置读取时亦归一为 coin."""
+    del raw
     return MODE_COIN
 
 
 def is_coin_margin_mode(raw: Any = None) -> bool:
-    return normalize_options_margin_mode(raw) == MODE_COIN
+    del raw
+    return True
 
 
 def inst_family_for_underlying(underlying: str, *, margin_mode: str | None = None) -> str: