/usr/lib/ghc-doc/hoogle/leksah-server.txt is in libghc-leksah-server-doc 0.12.1.2-3build2.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/ghc-doc/hoogle/../../../share/doc/libghc-leksah-server-doc/html/leksah-server.txt