chore: Support Angular 20 to 22

[jasny]

Summary

This PR expands the published Angular peer dependency range to support Angular 20, 21, and 22, and adds GitHub Actions coverage to test the package against each supported Angular major.

Changes

• widen Angular peer dependencies in playwright-ct-angular/package.json to >=20.3.11 <23.0.0
• update the package’s local Angular dev dependencies to Angular 22
• refresh pnpm-lock.yaml for the new dev dependency set
• update main.yml to run the test job as a matrix for Angular 20, 21, and 22
• add set-angular-version.js so CI can rewrite the sample app’s Angular package versions per matrix entry

Testing

• ran pnpm test locally with the Angular 22 dev dependency setup
• result: 45 passed

Notes

• CI uses the Angular major for the job name, while the script receives the full version range for dependency resolution
• the workflow uses pnpm install --no-frozen-lockfile because each matrix entry resolves a different Angular dependency graph