Improve folder structure for the frontend packages.

Created by: valerybugakov

Description

Frontend packages are mostly located inside of the client folder. Some of them are nested three levels deep. To make client packages location consistent we can move all the packages directly to the client folder. It will also allow having a simpler workspaces config.

Definition of success

• Packages in client folder are flattened.
• yarn workspaces are configured for client packages.

Notes

Part of the FE SDK Isolation RFC.