Change Regression Detector

Runs after every crawl. For each page where Historian found a direct content change, it compares the 24–48 hours after the change with the period before it: click rates on the page's elements, conversion rate and revenue. It looks at the pages that changed, not the whole site, so a regression on one checkout step is not drowned out by a good day elsewhere. When the numbers drop, the insight carries the evidence: the page, the element that changed, the kind of change (copy, image, order, removed or added), and the before-and-after figures — enough to decide whether to roll back without opening a dashboard.