Search HTML for per-100g calorie value using multiple strategies.
Strategy 1: ID-based lookup (quantity, 100g, per100g tabs).
Strategy 2: "100g" text markers + extractKcalFromSection + math validation.
Strategy 3: Pure math via findAllKcalInHtml - finds per-100g by arithmetic.
Search HTML for per-100g calorie value using multiple strategies.
Strategy 1: ID-based lookup (quantity, 100g, per100g tabs). Strategy 2: "100g" text markers + extractKcalFromSection + math validation. Strategy 3: Pure math via findAllKcalInHtml - finds per-100g by arithmetic.