Migrate React on Rails Pro CI from CircleCI to GitHub Actions (#1872)

Consolidates Pro package testing on GitHub Actions alongside the main package,
  creating 3 new workflow files to replace CircleCI configuration.

  ## Workflows Created

  - **pro-lint.yml**: RuboCop, ESLint, Prettier, TypeScript checks
  - **pro-package-tests.yml**: Jest unit tests, RSpec package tests, webpack builds
  - **pro-integration-tests.yml**: RSpec integration tests, Playwright E2E tests (with Redis)

Author: AbanoubGhadban