Booster bitswap MVP executable

[hannahhoward]

Goals

This is basically a "mashup" of booster-http, #377, and filecoin-project/dagstore#116 to kick the tires and see how to wire everything up for an independent boost executable.

Implementation

• Copy booster-http files
• Replace HTTPServer with bitswap server
• Migrate over the indexed blockstore from DAGStore PR and modify it to only use the available APIs
• Migrate over the piece selection function from [WIP] Bitswap integration in Boost #377, modify to not use go-fil-markets

TODO

• Tests, comments

For discussion

Key issues identified:

• dagstore.AcquireShard is not available on the API (and I assume it won't be) so that means unless a CarV2 was stored, we're going to be indexing every time we pull a shard. Perhaps this moves up the priority of PieceDirectory initial implementation #573 or associated efforts to make indexes more easily accessible
• I couldn't figure out pricing without moving over a lot of go-fil-markets machinery around asks. We probably need to consider the API for figuring out of if a deal is free.