fix(test): resolve TypeScript errors in test files

- Fix unused parameter warning in global-setup.ts
- Fix unknown error type in error handling
- Fix unused variable in test-runner.ts

All tests now compile without TypeScript errors.

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

Co-Authored-By: Claude <noreply@anthropic.com>

reactrebuild0825/tests/global-setup.ts

@@ -2,7 +2,7 @@ import { chromium, FullConfig } from '@playwright/test';
 import fs from 'fs';
 import path from 'path';
 
-async function globalSetup(config: FullConfig) {
+async function globalSetup(_config: FullConfig) {
   // Ensure screenshots directory exists
   const screenshotsDir = path.join(process.cwd(), 'screenshots');
   if (!fs.existsSync(screenshotsDir)) {
@@ -26,7 +26,7 @@ async function globalSetup(config: FullConfig) {
     await page.goto('http://localhost:5173', { waitUntil: 'networkidle' });
     console.log('✅ Application pre-warmed successfully');
   } catch (error) {
-    console.warn('⚠️ Could not pre-warm application:', error.message);
+    console.warn('⚠️ Could not pre-warm application:', (error as Error).message);
   } finally {
     await context.close();
     await browser.close();