website/docs: move Sources from Integrations into Docs (#9515)

* moved Sources form Integrations to Docs

* files moved

* fixed setting options

* fixed broken links and added redirects

* try single-sourcing Sources docs

* tweaks

* fighting links

* still fighting links

* fightng sidebar

* fighting with sidebar

* add logos and tweak

* image tweaks

* Optimised images with calibre/image-actions

* added remaining UI definitions

* kens edits

---------

Co-authored-by: Tana M Berry <tana@goauthentik.com>
Co-authored-by: authentik-automation[bot] <135050075+authentik-automation[bot]@users.noreply.github.com>

website/docs/sources/plex/index.md

@@ -0,0 +1,27 @@
+---
+title: Plex
+---
+
+<span class="badge badge--secondary">Support level: Community</span>
+
+Allows users to authenticate using their Plex credentials
+
+## Preparation
+
+None
+
+## authentik -> Sources
+
+Add _Plex_ as a _source_
+
+-   Name: Choose a name
+-   Slug: Set a slug
+-   Client ID: Set a unique Client Id or leave the generated ID
+-   Press _Load Servers_ to login to plex and pick the authorized Plex Servers for "allowed users"
+-   Decide if _anyone_ with a plex account can authenticate or only friends you share with
+
+Save, and you now have Plex as a source.
+
+:::note
+For more details on how-to have the new source display on the Login Page see [here](../general#add-sources-to-default-login-page).
+:::