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/compile/ref_error.ts

@@ -0,0 +1,13 @@
+import {resolveUrl, normalizeId, getFullPath} from "./resolve"
+import type {UriResolver} from "../types"
+
+export default class MissingRefError extends Error {
+  readonly missingRef: string
+  readonly missingSchema: string
+
+  constructor(resolver: UriResolver, baseId: string, ref: string, msg?: string) {
+    super(msg || `can't resolve reference ${ref} from id ${baseId}`)
+    this.missingRef = resolveUrl(resolver, baseId, ref)
+    this.missingSchema = normalizeId(getFullPath(resolver, this.missingRef))
+  }
+}