Load Shapes — Architecture

load_shapes lets a PA upload a ZIP of deemed 8760 load-shape data for a draft measure package, validates it in stages, saves it as DeemedLoadShape/LoadShapeHour rows, and (on request) turns it into impact_profiles.ImpactProfile records with avoided-cost quarterly costs that get shipped to CET. It is tightly coupled to impact_profiles (validation constants, ImpactProfile/ClimateZone/Hour/QuarterlyCost models, avoided-cost math) and to measure_packages (DraftMeasurePackage, LatestPermutation, the eTRM permutations an upload must match).