Revise whistleblower laws

This bill revises Montana's whistleblower protection laws by changing the burden of proof in retaliation claims. If an employee establishes a prima facie case of retaliation (e.g., for reporting workplace violations), the employer must prove by a preponderance of evidence that their action would have occurred regardless of the protected activity. In "mixed motive" cases - where retaliation occurred but the employer shows the action would have happened anyway - the employer may still recover damages. The changes apply to private-sector employees under Section 49-2-301 and public employees under Sections 39-2-904 and 49-3-209, directly affecting employees reporting violations and employers facing retaliation claims.