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/lib/refs/data.json

@@ -0,0 +1,13 @@
+{
+  "$id": "https://raw.githubusercontent.com/ajv-validator/ajv/master/lib/refs/data.json#",
+  "description": "Meta-schema for $data reference (JSON AnySchema extension proposal)",
+  "type": "object",
+  "required": ["$data"],
+  "properties": {
+    "$data": {
+      "type": "string",
+      "anyOf": [{"format": "relative-json-pointer"}, {"format": "json-pointer"}]
+    }
+  },
+  "additionalProperties": false
+}