Three scoping tiers (ledger-only / +Payment+Dispute / all five financial
models) with concrete time estimates grounded in actual reference counts
from the codebase. Recommends Option 1 (ledger only, 3–4 weeks) as the
right dual-DB shape if a forcing function appears, and explains why it's
not yet worth doing over the 2-week in-place hardening.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>