Slice 5b: update the FE-owned migration spec so the other repo can create the
bill columns in parallel.
- Bill block: per-section delivered kWh + cost (heating, hot water, lighting,
appliances, cooking, pumps/fans, cooling) + standing_charges_gbp,
seg_credit_gbp, total_annual_bill_gbp, fuel_rates_period.
- space_heating_kwh / water_heating_kwh (RHI recorded demand) marked SUPERSEDED
by heating_kwh / hot_water_kwh (calculator delivered fuel); kept until the bill
populates, then dropped.
- Cooling section kept (mostly 0 but affects the bill, cheap to store).
- Records the calculator-load-bearing posture (effective_* may differ from
lodged_* for pre-10.2) and that columns are defined now / populated when the
SapResult->EnergyBreakdown adapter + BillDerivation wiring land.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Make the stored units explicit on the property_baseline_performance columns:
- `*_co2_emissions` → `*_co2_emissions_t_per_yr` (tonnes CO₂/yr, whole dwelling)
- `*_primary_energy_intensity` → `*_primary_energy_intensity_kwh_per_m2_yr`
Column names only; the domain `Performance` VO stays unit-suffix-free (units are
a storage concern, mapped in from_domain/to_domain). Migration doc updated.
Round-trip stays green.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>