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/src/index.js

@@ -0,0 +1,10 @@
+/**
+ * Detect Electron renderer process, which is node, but we should
+ * treat as a browser.
+ */
+
+if (typeof process !== 'undefined' && process.type === 'renderer') {
+  module.exports = require('./browser.js');
+} else {
+  module.exports = require('./node.js');
+}