Support yarn workspaces, lerna packages

Yarn natively supports monoropos through a setting called workspaces. When using npm, a project called lerna has a packages setting.

• https://yarnpkg.com/lang/en/docs/workspaces/
• https://yarnpkg.com/blog/2017/08/02/introducing-workspaces/
• https://github.com/lerna/lerna#lernajson

The workspaces config in the root package.json, or packages in lerna.json lists glob patterns for all the workspaces.

If typesync is run in a project with workspaces, it would be great if it ran across all of the workspaces simultaneously.

A workaround is to run yarn lerna exec typesync to execute typesync in every package directory, but it’s much slower because it’s spawning a copy of typesync for each package.json. My repo has 40+ packages and lots of duplication between them.

[wldcordeiro]

This is pretty great, but with lerna at least most people would put all the type defs in the root devDependencies rather than spread across the packages. 🤷‍♂️

[jeffijoe]

I use neither, so I don’t know what people do and don’t do. 🤷‍♂️ Whatever the behavior needs to be, it needs to be consistent across both.