fix: descriptions

[kai687]

Extract the first sentence of the parameter description and uses it as help text.

I wrote the specs such that the first sentence is followed by an empty line, followed by more information. For the CLI, we can extract the first sentence and use it as help text.

I replace any Markdown links [link text](https://some/url) with link text,
so that it reads nicely in the terminal.

What do you think @clemfromspace ?

[clemfromspace]

Looks good, thanks @kai687!
I do not see any links in the generated flags anymore though, is that intended?

[kai687]

Good question! The links depend on the pages in the docs being there.
Currently there are no pages for semanticSearch, reRankingApplyFilter, or cursor,
so these links don't work.

I thought it would be too much of a dependency. Like, the flags themselves are coming from the specs and the links depend on the old docs. If we ever want to change that, we need to update the CLI as well.

For now, I could add back links to pages that exist. WDYT?

[clemfromspace]

@kai687 That sounds good 👍

[clemfromspace]

LGTM ✅

[kai687]

Thanks! Can't merge myself.