[Feature]: Allow users to pause and resume crawls

[SuaYoo]

What change would you like to see?

I'd like to be able to pause running crawls while I review and adjust crawl settings.

Context

Currently, once a crawl is running it can only be stopped or canceled. This results in numerous new crawls, even if I want a single replay for what I'm crawling.

Once #2514 is merged we'll be able to update crawl settings while a crawl is running, but it doesn't cover the case if I need to spend some time reviewing the paused crawl to know which settings to adjust.