* Add support for binary user properties in MQTT 5.0
* Optimize byte array reversal in SubscriptionTopicHashTests
* Use InvariantCulture for topic string conversion in Load_Tests
* switched to `Microsoft.Testing.Platform`
* Refactor CI workflow to separate signed and unsigned package builds
* Add condition to sign job to prevent execution on external pull requests
* Remove fallback to value as string in MqttUserProperty
* Refactor MqttUserProperty handling to use byte arrays for improved performance and add deprecation warnings for legacy methods