feat(web): add useIsClient hook for SSR-safe client detection

Author: gracefullight

apps/web/src/hooks/use-is-client.ts

@@ -0,0 +1,12 @@
+import { useSyncExternalStore } from "react";
+
+// biome-ignore lint/suspicious/noEmptyBlockStatements: noop function for subscribe
+const emptySubscribe = () => () => {};
+
+export function useIsClient() {
+  return useSyncExternalStore(
+    emptySubscribe,
+    () => true,
+    () => false
+  );
+}