[fix.research.ρ.D8+] harden the loop drawer under real interaction

Real Chrome exposed two distinct risks: asynchronous drawer refreshes could steal focus after close, and the acceptance harness shared receipts across scenarios while continuing after a failed recovery. Fence refresh epochs and campaign identity, make mutations single-flight with visibly disabled controls, isolate browser scenarios, and exercise approve, reject, double-click, rapid Escape, reload and 360px layouts. Visual inspection then showed rejection hidden below the fold, so terminal outcomes now state whether a RunSet completed unvalidated or a human rejected it without dispatch.

Author: ivanicu