Async indexing

[zachallaun]

Depending on the computer and size of the project being indexed, it was possible for indexing to take longer than the previous 20 second timeout. Additionally, since indexing was blocking the store GenServer, any calls made to the Store during a long indexing would be likely to time out (default GenServer call timeout is 5 seconds).

This PR updates the Store.State API to load asynchronously so that the store can continue to respond while indexing occurs in a task, while the indexing itself has had its timeout changed to :infinity.

[philipgiuliani]

I've tested it in a project which I couldn't use with Lexical because it was in an indexing loop. Using this branch it worked now and the LSP seems to be fully functional.

[scohen]

Note: if you want to change a name, I'm fine with that, but that should be done in a separate PR. A lot of this one is just renaming refresh to update, which makes it a lot harder to review.

[zachallaun]

Note: if you want to change a name, I'm fine with that, but that should be done in a separate PR. A lot of this one is just renaming refresh to update, which makes it a lot harder to review.

Yep, good point. I tend to best understand code by refactoring it, because it helps me understand what the code is doing and helps develop my mental model. In this particular case, I was initially thrown off by the use of refresh and update somewhat interchangeably, so I decided to normalize it to update. I agree that it should have been a separate PR, though.