Support module definitions by looking for file name

[AndrewNolte]

• Looks for symbol.sv in the repo when searching on hover and definition
• Package refs, modports follow their parent and search for that module/package/interface
• switched a bunch of stuff to async/await
• cleaned up logs

TODO (future work):

• This might leave indexed files in longer than they should be
• We should only be searching on module defs, not all symbols. It looks like we only find the kind of symbol defs, not any rhs
• have the async tasks race and cancel the lagging one

[AndrewNolte]

This PR should be good to go now @mshr-h

[mshr-h]

Thanks for your hard work. And sorry for the late reply. Looks like your idea is good to me. I'll merge it.