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/debug/.npmignore

@@ -0,0 +1,9 @@
+support
+test
+examples
+example
+*.sock
+dist
+yarn.lock
+coverage
+bower.json