Restructure the project

[TwitchBronBron]

The project structure is a bit confusing. There's a top-level folder that has...some stuff? But the actual plugin is under ./bsc-plugin, and then there's the ./framework folder which has the rooibos runtime code.

For the sake of contributors (and just to clean things up), we should move everything to the root of the project and eliminate the .code-workspace file entirely.