help-beta: Add MDX files to git.

We have not yet removed the help files. We can use this commit as a
conversion commit since a lot more help changes will be merged before
this PR gets merged. We will need to rebase on top of main, run
conversion step in this commit, push those changes and then merge the
PR.

NOTE: This commit temporarily breaks the astro build since we have
renamed the path in the MDX files from starlight_help/ to help/ early.
That should be fine since astro build will not break any tests right
now.
We should squash this commit with the next commit removing help center
files when merging into main and remove this NOTE.

starlight_help/src/content/docs/change-your-name.mdx

@@ -0,0 +1,29 @@
+---
+title: Change your name
+---
+
+import NavigationSteps from "../../components/NavigationSteps.astro"
+import ZulipNote from '../../components/ZulipNote.astro';
+import FlattenedSteps from '../../components/FlattenedSteps.astro';
+
+By default, everyone can change their name in Zulip. You can write your name
+in any language you'd like.
+
+Organization administrators can [change anyone's name](/help/change-a-users-name), and
+[prevent users from changing their names](/help/restrict-name-and-email-changes). This
+is useful when users' names are managed via LDAP or another data source.
+
+### Change your name
+
+<FlattenedSteps>
+  <NavigationSteps target="settings/profile" />
+
+  1. Edit the **Name** field.
+</FlattenedSteps>
+
+<ZulipNote>
+  **Note:** If you are unable to edit the name field, check
+  that your organization allows name changes. Follow the steps at
+  [prevent users from changing their names](/help/restrict-name-and-email-changes)
+  to view your organization's settings.
+</ZulipNote>