DOC-2597: Add link to official Uploadcare documentation for Signed Uploads

Author: Farzad Hayatbakhsh

modules/ROOT/partials/configuration/uploadcare_signed_upload_auth_provider.adoc

@@ -16,13 +16,19 @@ tinymce.init({
   plugins: 'uploadcare',
   toolbar: 'uploadcare',
   uploadcare_public_key: '<your-public-key>',
-  uploadcare_signed_upload_auth_provider: (_publicKey) => Promise.resolve({
+  uploadcare_signed_upload_auth_provider: (publicKey) => Promise.resolve({
     signature: 'sig',
     expire: 123
   }),
 });
 ----
 
+[TIP]
+.Starter Project
+====
+To get started quickly and understand how Uploadcare Signed Uploads integrates with {productname} {pluginname}, {companyname} recommends trying the starter project on GitHub to set up {pluginname} with Signed Uploads. Just clone the repository and follow the steps to set up the project. The link will take you to the GitHub page for the starter project, where the source code is available for you to view: link:https://github.com/tinymce/tinymce-uploadcare-signed-uploads-starter[{productname} {pluginname} Signed Uploads Starter Project].
+====
+
 [IMPORTANT]
 ====
 {companyname} recommends configuring the `uploadcare_signed_upload_auth_provider` option to secure uploads and prevent misuse of your Uploadcare `uploadcare_public_key`. This option is essential for applications requiring:
@@ -34,4 +40,4 @@ tinymce.init({
 This option **only** secures unauthorized access to upload files to the uploadcare storage by verifying signatures during uploads.
 
 For most integrations, enabling signed uploads by configuring this option ensures that only authorized uploads occur, reducing the risk of abuse and maintaining secure usage of your `uploadcare_public_key`.
-====
+====