[WIP] Update diffusers-cli for agentic use

[DN6]

What does this PR do?

Some updates to the diffusers-cli to make it more agent friendly. This PR

1. Adds a diffusers-cli skill to showcase the features available via the CLI and how to use them
2. Adds a describe command that can we used to extract the inputs of a pipeline from an input repo id
3. Adds a generate command that runs inference with any diffusers compatible pipelines. It also provides a number of optimization options (CP, cpu/group offload) + LoRA and allows running inference remotely on HF jobs.

Fixes # (issue)

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