feat: add manual bank card ledger

Store exact RUB balances, atomic transfers, linked refunds and versioned edits independently of T-Bank. Add migration, HTTP and durability verification.

src/tbank/bond.service.ts

@@ -12,14 +12,14 @@ import {
 } from '@nestjs/common';
 import { LRUCache } from 'lru-cache';
 import {
-  decimal,
   decimalFromString,
   divide,
   formatDecimal,
   multiply,
   subtract,
   add,
-} from './decimal';
+} from '../common/decimal';
+import { decimal } from './decimal';
 import { NcrRatingsClient } from './ncr-ratings.client';
 import { MoexClient } from './moex.client';
 import { PortfolioService } from './portfolio.service';