Hydration overlay

A mismatch that names data-cursor-ref comes from Cursor’s browser, which adds that attribute to links before React hydrates.

shell.tsx and standards-nav.tsx do not render data-cursor-ref. A search of this repository should not find it in source.

A normal browser does not inject the attribute, so the overlay should not appear there. The same class of mismatch can come from other injected attributes, such as webcrx.

Do not add suppressHydrationWarning to hide an attribute the app does not render.