docs(ai): inline docs for enums.ts

Author: russellwheatley

packages/ai/lib/types/enums.ts

@@ -1,6 +1,6 @@
 /**
  * @license
- * Copyright 2024 Google LLC
+ * Copyright 2025 Google LLC
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -202,6 +202,8 @@ export enum FinishReason {
 }
 
 /**
+ * Function calling mode for the model.
+ *
  * @public
  */
 export enum FunctionCallingMode {