chore: upgrade playwright to 1.62.1

[marcomaes]

Summary

• Bumps playwright-core/playwright/@playwright/test to 1.62.1 across all workspaces.
• playwright-core ≥1.60.0 dropped the separate internal files this repo required directly (lib/generated/injectedScriptSource.js, lib/utils/isomorphic/locatorUtils.js) in favor of one opaque lib/coreBundle.js. Adds a postinstall script (scripts/sync-playwright-injected-script.mjs) that auto-extracts the injected-script engine source from whatever playwright-core version is installed, and hand-vendors the small, stable selector-string builders in packages/mobilewright-core/src/selector-builders.ts — so future Playwright bumps stay low-effort instead of requiring a rewrite.
• Playwright's expect() web-first matchers now gate on receiver._apiName === 'Locator' instead of receiver.constructor.name; MobileWebViewLocator now sets _apiName so expect(locator).toBeVisible() etc. keep working.

Test plan

• npm run build
• npm run lint
• npm run test (597 passed, 1 skipped)
• Deleted packages/mobilewright-core/src/generated/ and re-ran npm install to confirm postinstall regenerates it from a clean state

🤖 Generated with Claude Code

[marcomaes]

Superseded by mobile-next#274 (PR against upstream).