feat(ai-copilot): support images with copilot models

[richter-mvtec]

What it does

Recently experimental support for copilot models via copilot sdk was added. The feature is missing support to send images.

This change will attach the images to the message send to the copilot sdk.

How to test

• Select a (multi-model) copilot model
• Attach an image to the conversation
• The LLM should be able to explain the content of the image

Follow-ups

• As currently the whole chat history is sent as one message and the images are attached to this message, there might be an impact on caching.

Breaking changes

Attribution

Contributed on behalf of MVTec Software GmbH

Review checklist

• As an author, I have thoroughly tested my changes and carefully followed the review guidelines

Reminder for reviewers

• As a reviewer, I agree to behave in accordance with the review guidelines