Numbers come straight from Meta's Marketing API each time the page loads or the dates change.
Amounts are in each account's own currency.
Outbound link click rate is Meta's outbound CTR: outbound clicks ÷ impressions.
Add to cart, checkout initiate and purchase rates are each of those events divided by landing page views.
Today, Yesterday and the day ranges follow each account's own time zone, the same way Ads Manager does. Custom dates are read in each account's time zone too.
Daily budget is the sum of active campaign budgets plus active ad set budgets right now; it doesn't change with the date range.