Are there tugnuts meant to fit forward facing horizontal dropouts such as those on a Surly Cross Check, All City Space Horse, or Salsa Cassaroll which won't block rack and fender bosses and keep wheel from sliding forward during heavy pedaling?
You can use a BMX chain tensioner, like this one, reversed, on some dropouts, but you will need to find one that works with your particular frame and dropout.
There is nothing designed for that purpose which I am aware of. However, If you are using proper torque, and proper track nuts, or nuts with washers, your wheel should not move in the dropout, with or without a tensioner.
Tensioners are designed to make it easier to align the wheel, and get proper tension on the chain, not to keep the wheel from slipping in the dropout.
If your wheel is slipping in the dropout, then there is something else wrong, in my opinion.