fix(badges): show 'already printed' notice to public users on print page

Without this, a public user who navigates to a printed badge's print page
sees a blank controls panel with no explanation. Now shows an amber notice
directing them to event staff. Gated on !can_print && is_printed && !is_trusted
so it never shows to staff.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/routes/events/[event_id]/(badges)/badges/[badge_id]/ae_comp__badge_print_controls.svelte

@@ -952,6 +952,16 @@ let allow_tracking_open = $derived(
     </div>
 {/if}
 
+<!-- Already-printed notice for public/attendee users who can't reprint.
+     Without this they see a blank controls panel with no explanation. -->
+{#if !can_print && is_printed && !is_trusted}
+    <div class="mb-2 rounded-lg border border-amber-200 bg-amber-50 px-3 py-2 text-center text-sm text-amber-800 dark:border-amber-800 dark:bg-amber-950/30 dark:text-amber-300">
+        This badge has already been printed.
+        <br />
+        <span class="text-xs opacity-70">Please see event staff if you need assistance.</span>
+    </div>
+{/if}
+
 <div class="space-y-1 text-sm">
     <!-- Attendee section header — clickable, collapses staff when opened -->
     <button