/usr/lib/ghc-doc/hoogle/web-routes.txt is in libghc-web-routes-doc 0.27.2-4build2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/ghc-doc/hoogle/../../../share/doc/libghc-web-routes-doc/html/web-routes.txt