Function isMsgTypeOutPayload

isMsgTypeOutPayload(payload: OutPayload): payload is MsgTypeOutPayload
Type guard function to determine if an OutPayload is a MsgType-based payload.

Checks whether the payload uses the legacy MsgType field format for message type identification. This is used to differentiate between different payload structures and ensure proper type narrowing in TypeScript.
Parameters
- payload: OutPayload
  The OutPayload to check
Returns payload is MsgTypeOutPayload
True if the payload is a MsgTypeOutPayload, false otherwise
- Defined in src/lib/PayloadTypeGuards.ts:14