Feature request - XML comments for intellisense

XML Comments for intellisense.

Currently to figure out what a method does I have to:

- Hope its in the docs
- Hope its in a guide
- Hope its in a sample (many samples/guides have very helpful comments in them)
- Launch Elsa Dashboard and read the comments in different UI screens
- Finally, read the source code

## No intellisense/XML comments screenshot


## Very helpful info, in UI


Also, I used a google site search `site:https://elsa-workflows.github.io "singleton"` and found AsSingle is documented, but on a hidden page:

https://elsa-workflows.github.io/elsa-core/docs/guides/guides-recurring-task

VS

https://elsa-workflows.github.io/elsa-core/docs/guides/guides-recurring-tasks