adds Authentication page content (#48)

* adds Authentication page content

* changes link about auth to the new API docs

src/pages/docs/features/authentication.md

@@ -3,4 +3,16 @@ title: Authentication
 description: Authenticating your users with Cirro.
 ---
 
-TODO
+To talk to the Cirro API you need to first register your app in the [Cirro developer portal](https://developers.cirro.io/).
+
+Once you have registered your app, you will receive your **app ID**.
+You then need to generate your apps **private key file** (PEM format).
+The developer portal allows you to generate this file and download it.
+The private key file is used to sign the JWT token that is sent with each API request.
+
+It should go without saying that you should keep your private key file secure.
+If you lose it, you will need to generate a new one in the developer portal and update your app to use the new key.
+With the private key file and app ID, you have full access to all API functions for your app, including managing
+Gigs, Users, and other app settings.
+
+Read more about how to use the private key file and app ID in the [API authentication documentation](https://api-docs.cirro.io/docs/authentication).

src/pages/index.md

@@ -32,4 +32,6 @@ Please be aware that the Guides are still in development. If you find any issues
 
 Latest changes to the Cirro Guides:
 
+- Oct 18, 2024 - Added Authentication page.
+- Oct 08, 2024 - Added AI Access page.
 - May 16, 2023 - Setting up the Cirro Guides.