React route consumers subscribed via useContributions(ROUTES_AREA) but
discarded its snapshot, deriving routes through an independent imperative
contributedRoutes() call. With React Compiler enabled the derived routes
could stay memoized across a late registration or hot replacement the
subscription DID deliver, so an installed plugin's page never mounted
while its sidebar entry did (#109063).
contributedRoutes() now accepts an explicit contribution snapshot,
defaulting to the registry read for imperative callers; both React
consumers (ChatRoutesSurface, RouteTilePane) pass their snapshot through.
liuhao1024
6fc7032aac