onElicitationRequest method
Register a handler for server-initiated elicitation/create
requests (spec 2025-06-18). The handler shows the requested form to
the user and returns { action, content? } per spec — action is
accept / decline / cancel.
Calling this advertises the elicitation client capability.
Implementation
void onElicitationRequest(
Future<Map<String, dynamic>> Function(Map<String, dynamic> params) handler,
) {
_requestHandlers['elicitation/create'] = handler;
}