Keep Tab inside the admin command menu

The search input is the only tabbable element in the menu, and Base UI's
focus guards let Tab leak out of a single-element trap: focus walked to
the sidebar while the menu stayed open. Arrow keys drive the selection
in a command menu, so Tab now stays on the input.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/components/admin/admin-command-menu.tsx

@@ -151,7 +151,18 @@ export function AdminCommandMenu({ onOpen }: { onOpen?: () => void }) {
             }}
           >
             <DialogPrimitive.Title className="sr-only">Поиск по админке</DialogPrimitive.Title>
-            <Command shouldFilter={false} label="Поиск по админке" loop>
+            <Command
+              shouldFilter={false}
+              label="Поиск по админке"
+              loop
+              // The input is the only tabbable element here, and Base UI's focus
+              // guards let Tab leak out of a single-element trap (seen live:
+              // focus walked to the sidebar while the menu stayed open). In a
+              // command menu arrows move the selection, so Tab simply stays put.
+              onKeyDown={(e) => {
+                if (e.key === "Tab") e.preventDefault();
+              }}
+            >
               <div
                 className="flex items-center gap-2 px-3"
                 style={{ borderBottom: "2px solid var(--border)" }}