Paid Measurement Loop Reads a paid-ads change back against a control over a fixed readback window and returns Promote / Keep-testing / Rollback / Unproven. This is the paid readback loop — distinct from (the ROI/CPA math, which this delegates to), (RQS score/veto adjudication), and (cross-channel rollup); it owns only the readback decision, window, and control. Quick Start Skill Contract Expected output : a per-change (Promote / Keep-testing / Rollback / Unproven) and Cycle Retro bound to the exact change/test head, artifact and measurement-contract hashes, with delta-vs-control on a primary…