This refactors the front-end collateral to all live within `site` - so no `package.json` at the root.
The reason we had this initially is that the jest test run and NextJS actually require having _two_ different `tsconfig`s - Next needs `jsx:"preserve"`, while jest needs `jsx:"react"` - we were using `tsconfig`s at different levels at the hierarchy to manage this.
I changed this behavior to still use two different `tsconfig.json`s, which is mandatory - but just side-by-side in `site`.
Once that's fixed, it was easy to move everything into `site`
Follow up from: https://github.com/coder/coder/pull/118#discussion_r796244577
This implements a simple Project listing page at `/projects` - just a table for a list of projects:

...and an empty state:

There isn't too much data to show at the moment. It'll be nice in the future to show the following fields and improve the UI with it:
- An icon
- A list of users using the project
- A description
However, this brings in a lot of scaffolding to make it easier to build pages like this (`/organizations`, `/workspaces`, etc).
In particular, I brought over a few things from v1:
- The `Hero` / `Header` component at the top of pages + sub-components
- A `Table` component for help rendering table-like UI + sub-components
- Additional palette settings that the `Hero`