Shares of Brentwood-based AAC Holdings Inc. climbed Monday following the company's settlement of criminal charges related to a 2010 patient death in California, a sign of investor confidence the company can move on from the legal drama. Still, the 4 percent climb — as of 2:13 p.m., shares were up to $17.62 — was not as significant as the dive the stock took last summer after the charges were announced (and more specifically, after investors betting against the stock suggested the company should've…