Feature: advanced configuration

Nobody has claimed this yet.

Currently, we have implemented the logic to parse the description with "Default image: ..." and use it on the UI side only.

However, to make it clearer and easier on a global level, and also to eliminate the need for setting an image in the CLT actions in GitHub, we can do better by moving this definition into the configuration of the project.

We already have the main pattern that utilizes the `.clt` folder and has `patterns` there with custom patterns.

We should consider how to add a config file and also ensure that we can utilize those values from the CLT tool properly when running tests.

Start by examining the existing .clt folder and its patterns for custom patterns, then trace how the CLT tool reads values when running tests. Define where project configuration belongs and ensure the default image and other configuration values are consumed by the tool rather than only by the UI. Done means the configuration works without setting the image in GitHub CLT actions and tests cover its use.

Written by the indexing model from the issue text.