Records both levers, the funding-pool design (and the per-file version that
dropped payslip_builder.go), the resolved memory-budget.ts exception, and the
two hermetic fixtures with their mutation matrix.
The CHANGELOG clause 'no longer trimmed while a smaller, weakly-related one is
included whole' was imprecise after CG-21: the smaller file often IS still
included whole now, when its share nearly covers it. Reworded to say what the
fix actually guarantees.