v0.5.1

Highlights

• The built-in node fixture now keeps its state and cache directories for the lifetime of a controller, so repeated start()/stop() cycles in the same test preserve data. The resolved paths are exposed via TENZIR_NODE_STATE_DIRECTORY and TENZIR_NODE_CACHE_DIRECTORY, making fault-injection and restart scenarios easier to script.
• The example project includes an updated node-fixture scenario that demonstrates how persistent state survives a restart, along with refreshed baselines.
• Reference and guide documentation now describe the fixture lifecycle, the new environment variables, and provide a scaffolded xxd runner example for teams building their own runners.