feat: add recent tools tracking via localStorage

apps/web/src/hooks/use-recent-tools.ts

@@ -0,0 +1,33 @@
+import { useSyncExternalStore } from "react";
+
+const STORAGE_KEY = "snapotter-recent-tools";
+const MAX_RECENT = 5;
+
+let listeners: Array<() => void> = [];
+
+function getSnapshot(): string[] {
+  try {
+    const raw = localStorage.getItem(STORAGE_KEY);
+    return raw ? JSON.parse(raw) : [];
+  } catch {
+    return [];
+  }
+}
+
+function subscribe(listener: () => void) {
+  listeners.push(listener);
+  return () => {
+    listeners = listeners.filter((l) => l !== listener);
+  };
+}
+
+export function recordRecentTool(toolId: string) {
+  const current = getSnapshot();
+  const updated = [toolId, ...current.filter((id) => id !== toolId)].slice(0, MAX_RECENT);
+  localStorage.setItem(STORAGE_KEY, JSON.stringify(updated));
+  listeners.forEach((l) => l());
+}
+
+export function useRecentTools(): string[] {
+  return useSyncExternalStore(subscribe, getSnapshot, () => []);
+}