IEC 61131-3 TIME/TOD now surface as TimeSpan (UA Duration); DATE/DT
surface as DateTime (UTC). The wire form stays UDINT — AdsTwinCATClient
post-processes raw values in ReadValueAsync and OnAdsNotificationEx,
and accepts native CLR types in ConvertForWrite. Added Duration to
DriverDataType (back-compat: existing switches default to BaseDataType
for unknown enum values) and mapped it to DataTypeIds.Duration in
DriverNodeManager.
Closes#306
Map LInt/ULInt to DriverDataType.Int64/UInt64 instead of truncating
to Int32. AdsTwinCATClient.MapToClrType already returns long/ulong
so the wire-level read returns the correct boxed types.
Closes#305