A 45-year-old man with a 25 pack-year smoking history has recurrent episodes of cough and sputum production. Spirometry shows an FEV1/FVC ratio of 0.60 and FEV1 70% predicted, with minimal reversibility. He has had two exacerbations requiring oral steroids in the past year. According to the 2023 Canadian Thoracic Society COPD pharmacotherapy guideline, which is the most appropriate long-term inhaled therapy?