Search invoices for reconciliation

Search invoices (faturas) for reconciliation, scoped to the POS/company of the bank movement being reconciled — NOT to the logged-in user's own POS.

Defaults to the movement's own store and widens to the whole company on request: the match is nearly always in the same store, but group-level payments do cross stores, and before this the wider set was unreachable.

Returns {"results", "total", "truncated", "window", "scope", "warning"} — every narrowing is echoed back, because a silently applied filter is what made the original bug invisible.