Fix: Handle non-dict DISPATCH payload data in payload_to_event

[Copilot]

RESUMED dispatches may carry data as an empty string instead of an object. payload_to_event previously unpacked payload.data as a mapping unconditionally, triggering TypeError: 'str' object is not a mapping during reconnect flows.

• Root cause

  • Event conversion assumed Dispatch.data is always dict and used **payload.data in both known and unknown event paths.

• Change

  • Normalize payload.data before model parsing:
    • use original value when it is a dict
    • otherwise ignore it ({})

• Behavior impact

  • Prevents reconnect-time parse failures for malformed/non-object dispatch payloads.
  • Keeps existing parsing behavior unchanged for valid dict payloads.

@staticmethod
def payload_to_event(payload: Dispatch) -> Event:
    EventClass = EVENT_CLASSES.get(payload.type, None)
    data = payload.data if isinstance(payload.data, dict) else {}
    if EventClass is None:
        log("WARNING", f"Unknown payload type: {payload.type}")
        event = type_validate_python(Event, {"event_id": payload.id, **data})
        event.__type__ = payload.type  # type: ignore
        return event
    return type_validate_python(EventClass, {"event_id": payload.id, **data})