THE DESK KILL SWITCH (Wave A) — stop (or resume) every bot on one desk. Session-owner scoped; 404 if the desk is not the caller's (cloak).

{"halted": true, "reason": "..."} stops every bot on the desk from OPENING anything, whatever its own spec or verdict says. {"halted": false} resumes and CLEARS the reason (a stale reason left lying around reads as a current one).

IT STOPS ENTRIES ONLY, and that is the design, not a softening. Open positions keep being marked and keep exiting on their stops. A kill switch that also froze the exits would leave a member unable to get OUT of the thing that scared them, which is the opposite of a safety control. Every bot reads the flag on its own next walk, so a halt takes effect within one tick and needs no per-bot write.