Clarify auto setting behavior thanks to issue #304

[zamn]

I was very confused why "auto" was not working the way I expected it to which caused a lot of confusion why I was receiving ton of node heap allocation limit errors.

The explanation here points out the documentation is misleading: https://github.com/pmizio/typescript-tools.nvim/issues/304#issuecomment-2457230327

Updating the docs to prevent future confusion.