Testing: Add rapid PBT for trace parser

[p-offtermatt]

Problem

A trace parser is very well suited to use PBT, e.g. via https://github.com/flyingmutant/rapid

This is not only important for the current JSON parser, but is also supposed to serve as a template for future trace formats, which should enable future parser/writer for other formats to be tested with minimal effort.

Closing criteria

The JSON writer/parser for e2e tests is tested with rapid.