The name for a built template is now the same everywhere: a compiled template. Publication responses return it as compiled, where they returned ir.
What you need to do. Read publication.compiled and publication.manifest.compiled. A brand's footer is one renderedFooter with html, text, and headCss, and the send removes its unsubscribe row when none applies. The two footer blocks are gone, so replace imports of BrandFooterBlock with BrandRenderedFooter.
The fields inside keep their shapes, and the type checker points at each place to change.