Circular dependencies cause typescript compilation to fail

[willdunklin]

I was running into an issue where boardgame.io several imports were failing as undefined.

After a bit of digging it seems like the project has many circular dependencies. I was able to visualize them in this graph generated by dependency-cruiser:

Each pair of yellow edges represents a circular dependency. Most seem to deal with types.ts, but many more seem to be structural. I'm not sure how easily resolvable these issues are, but it has crippled the use of typescript in my project unfortunately.