Framework: Move components from /shared back to /client

[seear]

The scope of the first stage of server-side rendering will be limited to the logged-out masterbar. Also, we will move to some technique for marking components safe to use server-side that does not involve the directory structure, whilst renaming /client to /app or similar.

Therefore, we can move any components not required for the logged-out master bar out of /shared and back to /client.

[ehg]

While we're doing this, let's add the @ssr-ready pragma to everything we know is compatible.