"""Finance domain — the unified spend ledger and reconciliation centre.

This domain owns the cross-stream **unified spend fact** layer that the
finance team uses to reconcile and slice all platform spend (cloud /
software / AI / procurement) along one consistent set of dimensions
(period × department × cost-centre × cost-type × vendor), normalised to
USD with a month-frozen FX rate.

It does NOT re-ingest raw cost data. The materialisation runs through
``app.core.coordinators.finance_spend_coordinator`` which is the only
sanctioned place to read across the cmdb / asset / ai_spending /
procurement domains (per the platform rule that domain modules don't
import each other). The finance domain itself holds:

* the persisted ledger (:mod:`app.domains.finance.models`),
* the month-frozen FX resolver (:mod:`app.domains.finance.fx`),
* the read/query + close/restatement service
  (:mod:`app.domains.finance.service`),
* and the HTTP surface (:mod:`app.domains.finance.router`).
"""