Fix rotate_key to return 200 with body instead of 204

ActionSet maps to PUT/204 which suppresses the response body. Changed
to ActionUpdate (PATCH/200) so the new API key is returned and
displayed by the CLI.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: bricef

internal/http/testdata/openapi.golden.json

@@ -1042,7 +1042,7 @@
       }
     },
     "/actors/{name}/rotate-key": {
-      "put": {
+      "patch": {
         "operationId": "actor_rotate_key",
         "parameters": [
           {
@@ -1055,7 +1055,7 @@
           }
         ],
         "responses": {
-          "204": {
+          "200": {
             "content": {
               "application/json": {
                 "schema": {

internal/model/operations.go

@@ -236,7 +236,7 @@ func Operations() []Operation {
 		// Actors
 		Create("/actors", "Create an actor").Name("actor_create").Role(RoleAdmin).
 			Input(CreateActorParams{}).Output(Actor{}).Build(),
-		CustomAction(ActionSet, "/actors/{name}/rotate-key", "Rotate an actor's API key").Name("actor_rotate_key").Role(RoleAdmin).
+		CustomAction(ActionUpdate, "/actors/{name}/rotate-key", "Rotate an actor's API key").Name("actor_rotate_key").Role(RoleAdmin).
 			Desc("Generate a new API key for the actor. The old key is immediately invalidated. The new key is returned in the response (shown once).").
 			Output(Actor{}).Build(),
 		Update("/actors/{name}", "Update an actor").Name("actor_update").Role(RoleAdmin).