A 62-year-old woman with a 15-year history of type 2 diabetes and albuminuric chronic kidney disease (eGFR 50 mL/min/1.73 m², urine albumin-to-creatinine ratio 45 mg/mmol) has persistent office blood pressures around 152/86 mm Hg despite non-pharmacological measures. According to Canadian guidelines, which single agent is the most appropriate first-line antihypertensive therapy for this patient?