Support Tesseract / OCR in Copilot Example

[davearlin]

Thanks to the community for these great examples. I added some support for rasterized image document importing in the Copilot example. Would be happy to submit a PR for this. The only question I have is whether or not to add the fairly large (~20MB) english training data file required or to simply add a readme.md with instructions on adding it to the "tessdata" folder that is now part of the CopilotChatWebApi project.

[alexchaomander]

@davearlin Would love to see a PR! I think rather than including it in the main repo, could you include documentation in a README for how to get download it?

[glahaye]

PR made it in.