container: hledger-flow: finish uniform fiat subaccounts

- For consistency across *all* hledger-flow accounts/rules.
- For future-proofing legacy finance (as related to #163).

container/src/hledger-flow/accounts/discover/discover-credit-shared.rules

@@ -1,6 +1,6 @@
 # docker-finance | modern accounting for the power-user
 #
-# Copyright (C) 2021-2024 Aaron Fiore (Founder, Evergreen Crypto LLC)
+# Copyright (C) 2021-2025 Aaron Fiore (Founder, Evergreen Crypto LLC)
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -19,18 +19,18 @@ fields date,date2,description,amount_,type,direction,subaccount
 
 date-format %m/%d/%Y
 
-account1 liabilities:discover:%subaccount
+account1 liabilities:discover:%subaccount:USD
 amount %amount_ USD
 
 comment type:%type, direction:%direction
 
 # Default equity
 if %direction ^IN$
-  account2 equity:discover:%subaccount:withdrawal:%type
+  account2 equity:discover:%subaccount:withdrawal:%type:USD
 
 # Default expenses
 if %direction ^OUT$
   amount -%amount_ USD
-  account2 expenses:discover:%subaccount:%type
+  account2 expenses:discover:%subaccount:%type:USD
 
 # vim: sw=2 sts=2 si ai et