feat(cucumber): add JUnit Platform engine support and runner parity (…

[PUSHPAK-JAISWAL]

What & why

This PR implements Phase 2 of the Cucumber modernization agreed with @shossain786 in #155.

Following the initial compiler warning cleanups in #157 (PR 1), this PR provides first-class support for executing Cucumber scenarios via cucumber-junit-platform-engine alongside legacy TestNG execution:

1. Quarantine skip parity across test runners:
   • When running Cucumber on the JUnit Platform, throwing TestNG's SkipException caused scenarios to be marked as FAILED (an unhandled runtime exception) rather than skipped.
   • Added dynamic runner detection in CucumberHooks: throws org.testng.SkipException when executing under TestNG and org.opentest4j.TestAbortedException when running under JUnit Platform.
   • Guarded context inspection with SeleniumBootContext.isInitialized() to handle early hook evaluation safely.
2. Suite lifecycle parity for JUnit Platform:
   • Enhanced SeleniumBootLauncherListener.testPlanExecutionStarted to mirror SuiteExecutionListener.onStart(): initializes ApiHealthChecker.clearCache(), PreConditionRegistry.loadAll(), and TestManagementReporter.getInstance().onSuiteStart().
   • Added AtomicBoolean suiteStarted guards to both SeleniumBootLauncherListener and TestManagementReporter to ensure suite start hooks are strictly idempotent if both JUnit extension hooks and launcher listeners fire.
3. Documentation:
   • Updated docs-site/docs/cucumber.md with setup and runner examples for both Option A: JUnit Platform Engine (Recommended) (@Suite, @IncludeEngines("cucumber")) and Option B: TestNG (Legacy / Backwards Compatible).
   • Clarified the deprecation lifecycle of BaseCucumberTest (supported through 3.x, planned for removal in 4.0.0).
4. Test coverage:
   • Added CucumberQuarantineTest testing TestNG skip behavior, JUnit Platform abort behavior, and an end-to-end launcher execution test verifying 1 aborted scenario with 0 failures.
   • Added unit tests in SeleniumBootLauncherListenerTest covering lifecycle idempotency and state reset across test plans.

Closes #155

Type of change

• Bug fix
• New feature (opt-in, aligned with the framework philosophy)
• Documentation
• Internal refactor / test coverage

Checklist

• All existing tests pass (mvn clean verify / mvn test)
• New behaviour is covered by unit tests
• No new external dependencies introduced without prior discussion
• Code follows existing conventions (no new frameworks, minimal abstraction)
• No breaking changes to @SeleniumBootApi public APIs (or a major version bump is justified below)
• Docs updated if user-facing behaviour changed (docs-site/)

Notes for reviewers

• Zero breaking changes: Existing TestNG suites extending BaseCucumberTest continue to run exactly as before with no changes required.
• Quarantine skip detection: CucumberHooks.isTestNgExecution() inspects org.testng.Reporter.getCurrentTestResult() != null. In unit and launcher engine tests, this cleanly distinguishes between TestNG runs and JUnit Platform runs.