fix(amber): serialize Cordn setup and explain the two approvals

src/components/crew/CordnNativePanel.tsx

@@ -884,6 +884,20 @@ export function CordnNativePanel({
               {copy.encryptedNote}
             </p>
 
+            {/* Amber needs one foreground approval for the device key and one
+                for the join request. Show the two translated step labels so the
+                second prompt is expected, not a mystery. */}
+            {native.interactiveHintVisible && !canCreate && (
+              <p className="mx-auto flex max-w-sm items-center justify-center gap-1.5 text-[11px] text-amber-300/80">
+                <KeyRound className="h-3 w-3 shrink-0" />
+                <span>Amber</span>
+                <span aria-hidden="true">·</span>
+                <span>{t('cordnUi.setupDevice')}</span>
+                <span aria-hidden="true">→</span>
+                <span>{t('cordnUi.requestJoin')}</span>
+              </p>
+            )}
+
             <div className="flex flex-wrap items-center justify-center gap-2">
               {canCreate ? (
                 <Button

src/hooks/useCordnNative.ts

@@ -256,7 +256,14 @@ export function useCordnNative({
     return () => clearInterval(id);
   }, [ready, group, interactive, canBackgroundPoll, refresh]);
 
+  // One coordinator operation at a time. With Amber every coordinator request
+  // is a foreground approval; a double-tap on "Set up" used to start two
+  // publish/join flows, which looked like Amber randomly opening twice and left
+  // one of the two requests to time out.
+  const runInFlight = useRef(false);
   const run = useCallback(async <T,>(fn: () => Promise<T>): Promise<T | undefined> => {
+    if (runInFlight.current) return undefined;
+    runInFlight.current = true;
     setBusy(true);
     setError(null);
     try {
@@ -265,6 +272,7 @@ export function useCordnNative({
       setError(err instanceof Error ? err.message : String(err));
       return undefined;
     } finally {
+      runInFlight.current = false;
       setBusy(false);
       setLastCheckedAt(Date.now());
     }