[www] remove subrooms from public template

apps/www/src/client/App.tsx

@@ -2045,9 +2045,9 @@ function RoomPage({
 
 /**
  * A room as anyone sees it: the same hero the owner's page draws, with the creator linked
- * to their profile in place of the upload control, then the room's public facts, the
+ * to their profile in place of the upload control, then the room's public facts and the
- * photos players took in it, and its subrooms — read-only, since nothing here is the
+ * photos players took in it — read-only, since nothing here is the viewer's to change.
- * viewer's to change.
+ * Staff also see its subrooms; the owner gets them on their own page instead.
  */
 function PublicRoomView({
 	room,
@@ -2131,6 +2131,9 @@ function PublicRoomView({
 				)}
 			</section>
 
+			{/* Staff only: a visitor has no use for the room's internals. The owner sees them on
+			    their own page (RoomDetail), never this one. */}
+			{isAdmin() && (
 				<section className="card">
 					<h2>Subrooms</h2>
 					{subRooms.length === 0 ? (
@@ -2152,6 +2155,7 @@ function PublicRoomView({
 						</ul>
 					)}
 				</section>
+			)}
 
 			{/* Staff only, and cosmetic: hidden for everyone else, but `rooms` checks the token's
 			    role itself on the DELETE. */}