java: Add explicit property names to constructor arguments

[mpkorstanje]

⚡️ What's your motivation?

To de-serialize messages a deserializer has to know what order the fields of a constructor are in. By default Java does not provide the parameter names for constructor arguments. They're purely positional. We do however include that information as debug symbols and de-serialisers are smart enough to read those. But they can be optimized out (cucumber/messages-cli#50) for smaller runtime images.

By adding an annotation with the property name, de-serialisers will be able to match constructor fields to values.

🏷️ What kind of change is this?

• ⚡ New feature (non-breaking change which adds new behaviour)

📋 Checklist:

• I agree to respect and uphold the Cucumber Community Code of Conduct
• I've changed the behaviour of the code
  • I have added/updated tests to cover my changes.
• My change requires a change to the documentation.
  • I have updated the documentation accordingly.
• Users should know about my change
  • I have added an entry to the "Unreleased" section of the CHANGELOG, linking to this pull request.