feat(mobile): improve pairing invite journey

apps/mobile/src/lib/pairedUnlockSeen.ts

@@ -0,0 +1,15 @@
+import AsyncStorage from "@react-native-async-storage/async-storage";
+
+const keyFor = (userId: string, coupleId: string) => `paired_unlock_seen_${userId}_${coupleId}`;
+
+export async function hasSeenPairedUnlock(userId: string, coupleId: string): Promise<boolean> {
+    return (await AsyncStorage.getItem(keyFor(userId, coupleId))) === "true";
+}
+
+export async function markPairedUnlockSeen(userId: string, coupleId: string): Promise<void> {
+    await AsyncStorage.setItem(keyFor(userId, coupleId), "true");
+}
+
+export async function clearPairedUnlockSeen(userId: string, coupleId: string | null): Promise<void> {
+    if (coupleId) await AsyncStorage.removeItem(keyFor(userId, coupleId));
+}