Proof of proveit.physics.quantum.algebra.prepend_num_ket_with_one_ket theorem

import proveit
theory = proveit.Theory() # the theorem's theory

%proving prepend_num_ket_with_one_ket

With these allowed/disallowed theorem/theory presumptions (e.g., to avoid circular dependencies), we begin our proof of
prepend_num_ket_with_one_ket:
(see dependencies)