Add object-oriented license client library (v0.0.2)

- Add LicenseClient with PSR-3 logging and PSR-6 caching support
- Add DTO classes: LicenseInfo, LicenseStatus, ActivationResult
- Add LicenseState enum for license status values
- Add comprehensive exception hierarchy for error handling
- Add PSR dependencies (psr/log, psr/cache, psr/http-client)
- Update README with usage examples
- Update CHANGELOG for v0.0.2

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/Exception/LicenseInactiveException.php

@@ -0,0 +1,9 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Magdev\WcLicensedProductClient\Exception;
+
+final class LicenseInactiveException extends LicenseException
+{
+}