A 55-year-old man on ICU has had a tracheostomy for 21 days. The team plans decannulation. He has passed a cuff-deflation test, tolerates capping for 48 hours, has effective cough, manageable secretions, and adequate swallow confirmed by SLT. Fibreoptic assessment shows no significant suprastomal granulation or tracheal stenosis. After decannulation, what immediate post-decannulation care is required?