Yes, although you should think of them more like combat medics or support classes. These characters may be better at healing than others, but they still have limited resources to work with and should still be spending most of their time fighting.
That said, everyone has a little bit of healing potential. When a character hits 0 health, they enter a downed state where they start bleeding out (unless they’ve taken so much damage they’ve blown past the death threshold of course). Friendly units can rescue a downed character and bring them back with a little health, or enemy units can execute them up close with any weapon to earn a little XP and prevent them from coming back.
Both executions and rescue actions take time and can be interrupted, so you have to decide if doing so is worth the risk. Some characters may be better at rescuing than others.