Automate an Electron application using Playwright's built-in Electron support

Steps

1. Install `playwright` (not `@playwright/test` alone) as it includes the Electron automation module. Import and launch: `const { _electron: electron } = require('playwright'); const app = await electron.launch({ args: ['path/to/main.js'] })`.
2. Obtain the first browser window: `const window = await app.firstWindow()` — this returns a Playwright `Page` object, and the full Playwright page API (locators, assertions, network interception) is available on it.
3. Evaluate code in the main Electron process (Node.js context): `const appPath = await app.evaluate(({ app }) => app.getAppPath())` — `app.evaluate` runs code in the main process, not the renderer.
4. Take a screenshot of the app window: `await window.screenshot({ path: 'screenshot.png' })`, or run any standard Playwright page interactions and assertions.
5. Close the app cleanly: `await app.close()` — this signals Electron to exit rather than just closing the window.