Implement Playwright

[ravinderk]

Description

This pull request implements the Playwright E2E test framework, including tests for critical flows.

List of E2E Tests

• Plugin Activation Without Errors
• Can see a message when the core plugin (WooCommerce) is not active
• Payfast Gateway Disabled with Non-ZAR Currency
• Payfast Plugin Compatibility with ZAR Store Currency
• Enable Payfast Option
• Title and Description Display
• Verify Merchant ID, Merchant Key, and Passphrase
• Verify Debug Email Configuration
• Verify Enable Logging Functionality
• Verify Logging when "Enable Logging" is Not Checked: Log creates for test transactions.
• Verify Payfast Payment Option Availability
• Verify Payfast Option Visibility
• Verify Payfast Payment Process
• Verify Payfast Payment Confirmation
• Verify Payfast Payment Failure Handling
• Verify ITN for Successful Payment Manual Test. In E2E tests, we are simulating ITN.
• Test Payfast Payment Method on Block-Based Checkout
• Test Subscription Product with PayFast Payment Gateway
• Renew Subscription via PayFast

Steps to Test

• E2E GitHub workflow behaves as described in the issue description
• E2E tests should pass locally. npm run env:start-local && npm run test:e2e-local

Documentation

• This PR needs documentation (has the "Documentation" label).

Changelog Entry

Dev - Add Playwright end-to-end tests.

Closes #128.

Todo

• After pull request merge, update the E2E test status of each test in the critical flow table.