docs: extreme-detail reference for the rest of Accounting

Chart of accounts, cost centers/budgets, dimensions, revenue mapping
manual screens, posting chains, accruals, gaps, opening entries/
reclassification, bank reconciliation, loans/documentary credits/
guarantees, settlements/billing, fiscal years/journal types/branch
fees, and the exact calculation logic behind every report screen
including all 5 financial statements — plus a status table for every
defect found and fixed or flagged along the way.