fix: FarStay 2B→1B 匹配设备固件，修正 parse_4c_params 偏移

src/dg430.py

@@ -398,7 +398,7 @@ def parse_4c_params(data: bytes) -> DG430FixtureParams | None:
     step_tol = payload[20] if len(payload) >= 21 else 0
     back_forth = payload[21] if len(payload) >= 22 else 0
     near_stay = _le16(payload, 22) if len(payload) >= 24 else 0
-    far_stay = _le16(payload, 24) if len(payload) >= 26 else 0
+    far_stay = payload[24] if len(payload) >= 25 else 0  # 1 字节
 
     return DG430FixtureParams(
         addr=addr,