JS: Fix PublicHttpAction type (#26345)

GitOrigin-RevId: 692af27663c8b9887c36f265913668b793eb54cf

Author: xixixao

src/server/registration.ts

@@ -350,7 +350,7 @@ export type RegisteredAction<
  * @public
  */
 export type PublicHttpAction = {
-  (ctx: GenericActionCtx<any>, request: Request): Response;
+  (ctx: GenericActionCtx<any>, request: Request): Promise<Response>;
   isHttp: true;
   isRegistered?: true;