Could a tail rotor serve as a spin breaker for winged aircraft? It seems that yaw, more than pitch or roll, creates the greatest wing asymmetry in a spin.
If the spin progresses to the point where it cannot be broken, some aircraft are equipped with parachutes to try to stop rotation and to get the nose pointed down. Some cannot be saved.

Tail rotors work well in helicopters, and are part of the design to control the (spinning wing) rotor yaw, and, such as the 180 knot MH-65 Dolphin, have the rotor built into the tail to save drag.

Could this work as a safety feature for GA aircraft?
At least one of two possible devices is regularly added before spin testing:


Jettisonable mass, for example by fixing a sandbag to the tail, or
a spin chute.


Spin chutes do what you propose in yaw, but what they mostly do is to pull the tail up so the angle of attack over the whole wing is reduced. This is equally achieved by jettisoning that extra mass at the tail: Now the more forward center of gravity will add a nose-down moment.

In both cases the lowered angle of attack restores roll damping on the wing. This is really what stops a spin, yaw is less of a problem here.