Creation of a How-to Guide for Using the Testbench

[fmallmann]

The goal is to create a comprehensive "How-to" guide for utilizing the Testbench. This documentation is intended for users of the Agentic Layer and should provide clear instructions on the following:

Installation: How to install the Testbench within a Kubernetes cluster.
Configuration: How to define and configure an experiment.
Execution: How to trigger and run an experiment.

The guide should serve as a practical manual to enable users to set up their testing environment and evaluate their agents efficiently.