/usr/share/perl5/Mail/Message/Construct/ is in libmail-box-perl 2.099-1.
This file is owned by root:root, with mode 0o755.
..
/usr/share/perl5/Mail/Message/Construct/Bounce.pm
/usr/share/perl5/Mail/Message/Construct/Bounce.pod
/usr/share/perl5/Mail/Message/Construct/Build.pm
/usr/share/perl5/Mail/Message/Construct/Build.pod
/usr/share/perl5/Mail/Message/Construct/Forward.pm
/usr/share/perl5/Mail/Message/Construct/Forward.pod
/usr/share/perl5/Mail/Message/Construct/Read.pm
/usr/share/perl5/Mail/Message/Construct/Read.pod
/usr/share/perl5/Mail/Message/Construct/Rebuild.pm
/usr/share/perl5/Mail/Message/Construct/Rebuild.pod
/usr/share/perl5/Mail/Message/Construct/Reply.pm
/usr/share/perl5/Mail/Message/Construct/Reply.pod
/usr/share/perl5/Mail/Message/Construct/Text.pm
/usr/share/perl5/Mail/Message/Construct/Text.pod