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/ajv/dist/vocabularies/draft2020.d.ts

@@ -0,0 +1,3 @@
+import type { Vocabulary } from "../types";
+declare const draft2020Vocabularies: Vocabulary[];
+export default draft2020Vocabularies;