The remedy provided under this title is not a substitute for and does not affect any remedy that is incident to the proceedings in the trial court or any remedy of direct review of the sentence or conviction. In a case in which a person challenges the validity of confinement under a sentence of imprisonment by seeking the writ of habeas corpus or the writ of coram nobis or by invoking a common law or statutory remedy other than this title, a person may not appeal to the Supreme Court of Maryland or the Appellate Court of Maryland. This subtitle does not bar an appeal to the Appellate Court of Maryland: in a habeas corpus proceeding begun under § 9–110 of this article; or in any other proceeding in which a writ of habeas corpus is sought for a purpose other than to challenge the legality of a conviction of a crime or sentence of imprisonment for the conviction of the crime, including confinement as a result of a proceeding under Title 4 of the Correctional Services Article.