Broadcast a notifications/prompts/list_changed to every client listening
on the standalone GET SSE stream, informing them the set of available
prompts changed (per the server/prompts List Changed Notification).
Returns the number of listeners reached; 0 when no GET stream is open.
Call after a runtime registerDynamicPrompt (or a removal). For the draft
protocol, the notification is suppressed unless a client opted in via
subscriptions/listen with promptsListChanged:true.
Broadcast a notifications/prompts/list_changed to every client listening on the standalone GET SSE stream, informing them the set of available prompts changed (per the server/prompts List Changed Notification). Returns the number of listeners reached; 0 when no GET stream is open. Call after a runtime registerDynamicPrompt (or a removal). For the draft protocol, the notification is suppressed unless a client opted in via subscriptions/listen with promptsListChanged:true.