website: Use Docusaurus Frontmatter for badges (#12893)

website/docs: Reduce redundant usage of badges. Move badge logic to components.

- Fix JSX class name warning.
- Remove duplicate titles.
- Flesh out `support_level` frontmatter.

website/docs/add-secure-apps/applications/index.md

@@ -6,12 +6,12 @@ Applications, as defined in authentik, are used to configure and separate the au
 
 When a user logs into authentik, they see a list of the applications for which authentik is configured to provide authentication and authorization (the applications that that they are authorized to use).
 
-Applications are the "other half" of providers. They typically exist in a 1-to-1 relationship; each application needs a provider and every provider can be used with one application. Applications can, however, use specific, additional providers to augment the functionality of the main provider. For more information, see [Backchannel providers](./manage_apps.md#backchannel-providers).
+Applications are the "other half" of providers. They typically exist in a 1-to-1 relationship; each application needs a provider and every provider can be used with one application. Applications can, however, use specific, additional providers to augment the functionality of the main provider. For more information, see [Backchannel providers](./manage_apps.mdx#backchannel-providers).
 
 Furthermore, the [RAC (Remote Access Control)](../providers/rac/index.md) feature uses a single application and a single provider, but multiple "endpoints". An endpoint defines each remote machine.
 
 :::info
-For information about creating and managing applications, refer to [Manage applications](./manage_apps.md).
+For information about creating and managing applications, refer to [Manage applications](./manage_apps.mdx).
 :::
 
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