/live answers {type:'who'} with who is here: usernames, guest names with their colour, and driving, queued or watching - lobby and test only #371

Replaces #363, which was parked only because it inherited a blocker on #291 (closed as split). This one waits only on what it names. Rewritten from #292, piece 2 of 3.

Done:

• [ ] On {type:'who'} the lobby answers that socket alone with {type:'who', people:[{name, colour?, guest:boolean, role:'driving'|'queued'|'watching'}]}. A signed-in person with two tabs is listed once. At most one request per second per socket is answered.
• [ ] No address, user agent or user id is in the frame.
• [ ] Tests: the driver is marked driving, a queued user is queued, a guest has its colour, and a second request within a second is not answered.
• [ ] forge.json untouched, and bun --cwd Software/so101 test passes.

duplicate of #363