Add FDL deprecation FAQ link

Author: NhienLam

docs-devsite/auth.actioncodesettings.md

@@ -49,7 +49,7 @@ android?: {
 
 > Warning: This API is now obsolete.
 > 
-> Firebase Dynamic Links is deprecated. Instead, use `linkDomain` to set a custom domain for mobile links.
+> Firebase Dynamic Links is deprecated and will be shut down as early as August 2025. Instead, use  to set a custom domain for mobile links. Learn more in the [Dynamic Links deprecation FAQ](https://firebase.google.com/support/dynamic-links-faq)<!-- -->.
 > 
 
 When multiple custom dynamic link domains are defined for a project, specify which one to use when the link is to be opened via a specified mobile app (for example, `example.page.link`<!-- -->).

packages/auth/src/model/public_types.ts

@@ -507,8 +507,9 @@ export interface ActionCodeSettings {
    *
    * @defaultValue The first domain is automatically selected.
    *
-   * @deprecated Firebase Dynamic Links is deprecated. Instead, use `linkDomain` to set a custom
-   * domain for mobile links.
+   * @deprecated Firebase Dynamic Links is deprecated and will be shut down as early as August
+   * 2025. Instead, use {@link linkDomain} to set a custom domain for mobile links. Learn more in
+   * the {@link https://firebase.google.com/support/dynamic-links-faq | Dynamic Links deprecation FAQ}.
    */
   dynamicLinkDomain?: string;
   /**