To make a long story short ... About 10 years ago had an electrician add
a subpanel in my then new workshop (state of Virginia). He placed a 30
amp breaker in my main box and used that breaker to feed the subpanel in
the shop. Wiring was run in such a way that if 220v was ever needed it
would be a simple matter to get it to the work area. Now I am
attempting to sell my house and the inspector says "double taps on a
circuit breaker are not allowed." I think the electrician just placed
the "extra" wire there to keep it from floating around in the panel but
leave it available if 220 was ever desired. I guess I have 3 questions.

Are double taps on a circuit breaker against the NEC?

If double taps are permissible under the NEC, does anyone happen to have
the reference handy?

If it is against the NEC, can a pigtail be used to join the 2 wires and
then connect the pigtail to the circuit breaker?

Would appreciate any other thoughts. Thanks a bunch.