fix: Add debounced Undo/Redo system to avoid character-by-character history

- Add debounced state updates for title and content (500ms delay)
- Immediate UI updates with delayed history saving
- Prevent one-letter-per-undo issue
- Add cleanup for debounce timers on unmount

mcp-server/node_modules/hono/dist/utils/concurrent.js

@@ -0,0 +1,39 @@
+// src/utils/concurrent.ts
+var DEFAULT_CONCURRENCY = 1024;
+var createPool = ({
+  concurrency,
+  interval
+} = {}) => {
+  concurrency ||= DEFAULT_CONCURRENCY;
+  if (concurrency === Infinity) {
+    return {
+      run: async (fn) => fn()
+    };
+  }
+  const pool = /* @__PURE__ */ new Set();
+  const run = async (fn, promise, resolve) => {
+    if (pool.size >= concurrency) {
+      promise ||= new Promise((r) => resolve = r);
+      setTimeout(() => run(fn, promise, resolve));
+      return promise;
+    }
+    const marker = {};
+    pool.add(marker);
+    const result = await fn();
+    if (interval) {
+      setTimeout(() => pool.delete(marker), interval);
+    } else {
+      pool.delete(marker);
+    }
+    if (resolve) {
+      resolve(result);
+      return promise;
+    } else {
+      return result;
+    }
+  };
+  return { run };
+};
+export {
+  createPool
+};