docs: note the three illustrations added to the admin guide

docs/ADMIN-GUIDE.md

@@ -25,6 +25,8 @@ A browser certificate warning means that machine does not yet trust the local au
 
 **On site** is the tab you will live in. It lists everyone currently signed in, with their host, the time they arrived and how long they have been here.
 
+> *Illustration in the online guide: the On site tab, with placeholder visitors.*
+
 Three things you can do from each row:
 
 - **Sign out** — for the visitor who walked out without touching the kiosk.
@@ -59,6 +61,8 @@ Five wrong PINs locks that mobile number for 15 minutes. Saving the record clear
 
 **WWCC and VIT expiry.** Give a recurring visitor an expiry date and the console watches it. Inside 28 days the row turns amber; past the date it turns red, a count appears on the **Recurring visitors** tab, and a banner sits across the top of every screen. Nothing is blocked automatically — an expired check is a conversation at the desk, not a door the software slams.
 
+> *Illustration in the online guide: the recurring visitors list, one check expiring and one expired.*
+
 ## Settings worth knowing
 
 Almost everything a site needs sits under **Sites → Edit**. Each site has its own staff list, its own badge settings and its own look.
@@ -74,6 +78,8 @@ Almost everything a site needs sits under **Sites → Edit**. Each site has its
 
 **Before committing a new roll**, use **Bitmap preview** (shows the exact image that will be sent) and **Test print** on the site card.
 
+> *Illustration in the online guide: a 62 × 90 mm badge with every element labelled.*
+
 ### The evacuation sheet
 
 The Google Sheet exists for one job: so somebody standing in a car park can see who is in the building. Check it from **System → Test the sheet connection**, which also shows the service account address and the last successful write.