Add ui/notifications/request-teardown notification for view-initiated termination (#215)

* Add ui/close-resource request for UI to initiate termination

* Add missing METHOD export

* Fix typo in remaining ui/request-close

* Align spec terminology to teardown/termination instead of close/clearnup

* Implement final comments

* Removing view behavior on initiation of request termination

src/generated/schema.ts

@@ -478,6 +478,19 @@ export const McpUiSupportedContentBlockModalitiesSchema = z.object({
     .describe("Host supports structured content."),
 });
 
+/**
+ * @description Notification for app-initiated teardown request (View -> Host).
+ * Views send this to request that the host tear them down. The host decides
+ * whether to proceed - if approved, the host will send
+ * `ui/resource-teardown` to allow the view to perform cleanup before being
+ * unmounted.
+ * @see {@link app.App.requestTeardown} for the app method that sends this
+ */
+export const McpUiRequestTeardownNotificationSchema = z.object({
+  method: z.literal("ui/notifications/request-teardown"),
+  params: z.object({}).optional(),
+});
+
 /**
  * @description Capabilities supported by the host application.
  * @see {@link McpUiInitializeResult `McpUiInitializeResult`} for the initialization result that includes these capabilities