Condense ai imports into single line

Combine getToolName, isToolUIPart, and UIMessage type imports from 'ai' into a single-line import for cleaner formatting and reduced vertical whitespace; no functional change.

Author: threepointone

src/app.tsx

@@ -1,11 +1,7 @@
 import { Suspense, useCallback, useState, useEffect, useRef } from "react";
 import { useAgent } from "agents/react";
 import { useAgentChat } from "@cloudflare/ai-chat/react";
-import {
-  getToolName,
-  isToolUIPart,
-  type UIMessage,
-} from "ai";
+import { getToolName, isToolUIPart, type UIMessage } from "ai";
 import type { MCPServersState } from "agents";
 import type { ChatAgent } from "./server";
 import {