Proof of proveit.trigonometry.sine_linear_bound_by_arg_neg theorem

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

%proving sine_linear_bound_by_arg_neg

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