Add document-review UIWorker example

Synthesis example: a ReplyToolMixin UIWorker adds a start_review tool that fans
out to clarity/tone peers via start_user_job_group, translates each reviewer
response into an add_note command in on_job_response, handles a client
note_click event via @on_ui_event, and keeps history across turns.

examples/multi-worker/ui-worker/document-review/client/package.json

@@ -0,0 +1,18 @@
+{
+  "name": "document-review-client",
+  "private": true,
+  "version": "0.1.0",
+  "type": "module",
+  "scripts": {
+    "dev": "vite",
+    "build": "vite build",
+    "preview": "vite preview"
+  },
+  "dependencies": {
+    "@pipecat-ai/client-js": "1.9.0",
+    "@pipecat-ai/small-webrtc-transport": "^1.10.2"
+  },
+  "devDependencies": {
+    "vite": "^8"
+  }
+}