Mirror the BudgetVsActualTable structure in the Actual-vs-Actual compare
mode so MoM and YoY both surface a Monthly block (reference month vs
comparison month) and a Cumulative YTD block (progress through the
reference month vs progress through the previous window).
- CategoryDelta gains cumulative{Previous,Current}Amount and
cumulativeDelta{Abs,Pct}. Legacy previousAmount / currentAmount /
deltaAbs / deltaPct are kept as aliases of the monthly block so the
Highlights hub, Cartes dashboard and ComparePeriodChart keep working
unchanged.
- getCompareMonthOverMonth: cumulative-previous window ends at the end
of the previous month within the SAME year; when the reference month
is January, the previous window sits entirely in the prior calendar
year (Jan → Dec).
- getCompareYearOverYear: now takes an optional reference month
(defaults to December for backward compatibility). Monthly block
compares the single reference month across years; cumulative block
compares Jan → refMonth across years.
- ComparePeriodTable rebuilt with two colspan header groups, four
sub-columns each, a totals row and month/year boundary sub-labels.
- ComparePeriodChart unchanged: still reads the monthly primary fields.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
