feat: sign-in nip7

src/hooks/login.tsx

@@ -0,0 +1,12 @@
+import { useSyncExternalStore } from "react";
+import { Login } from "../login";
+
+export default function useLogin() {
+  return useSyncExternalStore(
+    (c) => {
+      Login?.on("change", c);
+      return () => Login?.off("change", c);
+    },
+    () => Login,
+  );
+}