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/common/money.dto.ts

@@ -0,0 +1,9 @@
+import { ApiProperty } from '@nestjs/swagger';
+
+export class MoneyDto {
+  @ApiProperty()
+  currency: string;
+
+  @ApiProperty()
+  value: string;
+}