RLS build logic reacts to didChange notifications by building immediately.

This isn't ideal because changes are soon followed by friends & the R in RLS stands for "Really slow compiling".

Let me demonstrate:

Here Rls handles a long compile time by doubling it and showing a meaningless error at half time. (The error you'd get from the first character typed).

Options

• Change to simply debounce on didChange, in a non-eager way, using the wait_to_build duration.
• Interact with rustc via a seperate process so it can be killed & replaced when a new request appears.

Hopefully that makes sense, any other ideas to improve this?