End a chatroom. Creator or school staff only.

The room is CLOSED here: status, ended_at, presence and join times, so a join that arrives a millisecond later gets a 410 and nobody is billed twice. Everything the end used to do inside this request — bill each participant, finalise the CallSession, stop the recording, close the breakouts, delete the LiveKit rooms — is queued (app.core.deferred) and done by the consumer. On 2026-09-08 ending a 25-student room held one pod for 261 s at the exact moment the next class was arriving.