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/prisma/build/public/assets/refresh.d5448ccc.svg

@@ -0,0 +1,4 @@
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+  <path fill="currentColor"
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+</svg>