The dev-only demo page shipped routable in the production assembly. Its route
moves from @page to a code-behind [Route] under #if DEBUG, so a Release build
keeps the component type (nothing referencing it breaks) but has no /dev/*
route. The page-authorization guard classifies it under #if DEBUG, and
DevRouteGatingTests asserts each configuration's half (Debug: exactly the demo
route; Release: none) with a positive control. Both configurations pass.
Refs #745
Claude-Session: https://claude.ai/code/session_01Ub9hGmYLQvn9XETzw7CMsT
Joseph Doherty