A 2-year-old girl from urban Delhi is brought to the emergency department with a 2-day history of acute watery diarrhea (6–8 stools/day) and mild vomiting. On examination: alert and playful, eyes normal, oral mucous membranes slightly dry, skin turgor normal, capillary refill <2 seconds. Weight before illness was 14 kg; current weight is 13.6 kg. Serum electrolytes: Na⁺ 138 mEq/L, K⁺ 3.8 mEq/L, Cl⁻ 102 mEq/L, HCO₃⁻ 20 mEq/L. Urine output is adequate. What is the most appropriate management?