docs(versioning): add versioning for version 1.13.1

Author: Meierschlumpf

versioned_docs/version-1.13.1/advanced/_category_.json

@@ -0,0 +1,9 @@
+{
+  "label": "Advanced",
+  "collapsed": true,
+  "position": 4,
+  "link": {
+    "type": "generated-index",
+    "title": "Advanced Concepts or features"
+  }
+}

versioned_docs/version-1.13.1/advanced/command-line/_category_.json

@@ -0,0 +1,4 @@
+{
+  "collapsed": true,
+  "label": "Command line interface"
+}

versioned_docs/version-1.13.1/advanced/command-line/fix-usernames/img/screenshot-cli.png

@@ -0,0 +1,17 @@
+# Fix usernames
+
+:::info
+
+This guide requires that you understand [how to access the CLI](../).
+
+:::
+
+If you somehow get into a situation where you have users with usernames that contain uppercase characters and you are no longer able to log in, you can use the following command to fix the usernames.
+
+```bash
+homarr fix-usernames
+```
+
+This will convert all credential usernames to lowercase and update the database accordingly.
+
+![](./img/screenshot-cli.png)