Allow multi threading keywords in article creator

1. The problem

AI threading only works for multiple ai articles per keyword.

If one article per keyword, no additional threading is used.

So with a big keyword list
700 keywords - 1 article.

It slows down to 1 article at a time instead of being able to run multiple requests.

In next update

Keywords → Page Inputs

Because, we are not just sending in one keyword, but a bunch of other macro data to the page pipeline.

This means that it will run your keywords in parallel.

The older AI related threads are set to 1 and hidden.

Multiple AI article counts are no longer parallel

Multiple prompts in ai main are no longer parallel

This just makes it easier to work with