docs(admin): add WHP super-admin section (5 draft articles)

Adds /whp/admin/ with: overview, server-settings, coraza-waf,
site-monitoring, user-management. Articles are product-neutral
(no VDS in titles or required framing) since super admin may be
offered as a separate service later. They're marked Draft via:

- 'Draft' sidebar badge on the group + each article
- A draft callout partial at the top of every page noting WIP

The super-admin-callout partial (renamed from vds-only-callout)
mentions VDS as today's most common way to get super admin without
locking the docs to that single product.

src/content/partials/draft-callout.mdx

@@ -0,0 +1,5 @@
+import { Aside } from '@astrojs/starlight/components';
+
+<Aside type="caution" title="Draft — work in progress">
+  This page is a draft. Some details may not match the panel yet, and screenshots are still pending. We're publishing it as a placeholder so the structure is in place; we'll fill in the gaps as we go.
+</Aside>

src/content/partials/super-admin-callout.mdx

@@ -0,0 +1,3 @@
+<div class="anhh-accent-callout">
+  **Requires WHP super admin access.** These features are unlocked for customers with a WHP super admin role on the server — for example, anyone running a [Virtual Dedicated Server](https://anhonesthost.com/vds). Customers without super admin won't see these pages.
+</div>