Except as otherwise provided by law, a custodian shall allow a person or governmental unit to inspect any public record at any reasonable time. Inspection or copying of a public record may be denied only to the extent provided under this title. To protect public records and to prevent unnecessary interference with official business, each official custodian shall adopt reasonable rules or regulations that, subject to this title: govern timely production and inspection of a public record; and prevent unauthorized disclosure or inspection of a public record, including in accordance with § 4–320.1 of this title. Each official custodian shall: designate types of public records of the governmental unit that are to be made available to any applicant immediately on request; and maintain a current list of the types of public records that have been designated as available to any applicant immediately on request.