lighteval-exercises

Refactor LightEval examples: update CLI commands and streamline output directory usage in README

Expand workshop README: clarify structure with presentation details and coding exercises

Enhance README with slides, images, and sponsorship information; add linked resources for workshop support.

Update fine-tuning README and script: improve instructions, add advanced exercises, and refine training configurations

Refactor LightEval examples: simplify configurations, update CLI commands, and improve task and model setup