Puffmutti

Pretty simple plugin: Will dismount the player, when the range to the bots current destination is below the value set in the plugins settings.
I use it in my quester profiles for bots that have access to mounts, so they don't mindlessly charge to a quest objective while being mounted, pull a dozen of mobs in the process, dismount when standing directly before the objective and just die to the group of mobs still following.
Also works with Druids Travel Form.