Remove unused imports in example apps

- `basic-server-react`: Remove unused `McpUiResourceTeardownResult`
- `customer-segmentation-server`: Remove unused `PostMessageTransport`

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <[email protected]>

Author: jonathanhefner

examples/basic-server-react/src/mcp-app.tsx

@@ -1,7 +1,7 @@
 /**
  * @file App that demonstrates a few features using MCP Apps SDK + React.
  */
-import type { App, McpUiResourceTeardownResult } from "@modelcontextprotocol/ext-apps";
+import type { App } from "@modelcontextprotocol/ext-apps";
 import { useApp } from "@modelcontextprotocol/ext-apps/react";
 import type { CallToolResult } from "@modelcontextprotocol/sdk/types.js";
 import { StrictMode, useCallback, useEffect, useState } from "react";

examples/customer-segmentation-server/src/mcp-app.ts

@@ -3,7 +3,6 @@
  */
 import {
   App,
-  PostMessageTransport,
   applyHostStyleVariables,
   applyHostFonts,
   applyDocumentTheme,