ShelfWidgetContentHeight
How tall the widget's card should be inside the shelf.
enum ShelfWidgetContentHeight
Both cases describe the card: the area the widget draws in, in points at the Regular shelf size, the same number the harness renders it at. The shelf adds its own slot inset and chrome around it, and the Enlarged shelf size scales the card with everything else. A paired row honours the same height, so a widget with a compact composition declares the height that composition needs too. The height includes contentInsets, so content sized to fit exactly budgets 16pt for it under the host's 18pt card corner and none alone on the island.
Cases
ShelfWidgetContentHeight.standard
case standard
The shelf's standard card height, shelfWidgetStandardContentHeight points.
ShelfWidgetContentHeight.fixed(_:)
case fixed(CGFloat)
A fixed card height in points, clamped to shelfWidgetFixedContentHeightRange.