feat: support ingesting GitHub issues

[jafarinia]

Hi.

Thank you for the wonderful repo. I think if you had the capability to see all the issues too, it would be really nice since there are cases that we need to find something on an issue and if the repo has many issues, finding the related issues is sometimes very difficult.

[cyclotruc]

Hey thank you for the kind words, this is a good idea I will think about how to implement it once we have a proper github integration