add a "move only" click command

Recently I have been trying to change my mouse controls. I have an extra button on it, and I would like to use only that button for attacks, and use right click for movement only. I was trying to look for a movement only option, and I couldn't find one.

Could this be added to the options? It seems really useful now that there are plants on the ground in the jungle that I keep accidentally clicking on. Accidentally attacking something when you meant to run for your life really sucks.