Add Playwright E2E testing with recorded workflows

- Add @playwright/test as dev dependency
- Create playwright.config.ts with Chrome-only testing config
- Add npm scripts: test:record, test:e2e, test:replay
- Create 13 test recordings covering:
  - 2-player and 3-player games
  - 8-ball, 9-ball, and 10-ball game types
  - Various race-to values (1, 3, 5, 7, 9) and "endlos" mode
  - Both wechselbreak (alternating) and winnerbreak rules
- Fix Infinity handling in gameService.ts and NewGameScreen.tsx
  - Parse "endlos" and "Infinity" strings as Infinity number
  - Properly serialize Infinity as string in form data
- Increase GameDetail score font size from 20vh to 40vh
- Update README.md with testing documentation:
  - Quick start guide for recording and running tests
  - Move E2E testing from "Future Improvements" (now implemented)
- Add comprehensive tests/recordings/README.md documentation

Purpose: Establishes browser automation testing infrastructure with
real workflow recordings, enabling regression testing and interaction
documentation for all game configuration combinations.

playwright.config.ts

@@ -0,0 +1,64 @@
+import { defineConfig, devices } from '@playwright/test';
+
+/**
+ * Playwright configuration for BSC Score browser automation
+ * Configured to work with local dev server on port 3000
+ */
+export default defineConfig({
+  // Test directory - where your recorded scripts live
+  testDir: './tests/recordings',
+  
+  // Match all .ts files in the recordings directory (not just .test.ts or .spec.ts)
+  testMatch: '**/*.ts',
+  
+  // Maximum time one test can run for
+  timeout: 30 * 1000,
+  
+  // Test execution settings
+  fullyParallel: false, // Run tests sequentially to avoid conflicts
+  forbidOnly: !!process.env.CI,
+  retries: process.env.CI ? 2 : 0,
+  workers: 1, // Run one at a time for recordings
+  
+  // Reporter configuration
+  reporter: 'html',
+  
+  // Shared settings for all tests
+  use: {
+    // Base URL for tests
+    baseURL: 'http://localhost:3000',
+    
+    // Browser context options
+    trace: 'on-first-retry',
+    screenshot: 'only-on-failure',
+    
+    // Viewport size
+    viewport: { width: 1280, height: 720 },
+  },
+
+  // Configure projects for different browsers
+  projects: [
+    {
+      name: 'chromium',
+      use: { ...devices['Desktop Chrome'] },
+    },
+    // Uncomment to add more browsers
+    // {
+    //   name: 'firefox',
+    //   use: { ...devices['Desktop Firefox'] },
+    // },
+    // {
+    //   name: 'webkit',
+    //   use: { ...devices['Desktop Safari'] },
+    // },
+  ],
+
+  // Web server configuration - starts dev server automatically if needed
+  // webServer: {
+  //   command: 'npm run dev',
+  //   url: 'http://localhost:3000',
+  //   reuseExistingServer: !process.env.CI,
+  //   timeout: 120 * 1000,
+  // },
+});
+