fix(reports): drop the kr suffix from invoice-currency AR-ledger columns (#1180)

Fixes #1172. The Fakturor sheet's Totalt/Betalt/Utestående columns are
invoice-original currency (the sheet carries a Valuta column and a
separate SEK-converted Utestående (SEK) column), yet used the
kr-suffixed currency format, so a EUR invoice rendered "1 000,00 kr"
beside Valuta=EUR. They now use the suffix-free decimalColumn added in
#1166; the SEK column and the SEK-converted aging sheet keep kr. The
supplier-ledger xlsx was checked: its buckets are SEK-converted via
resolveSekAmount, so kr is correct there.

Co-authored-by: Claude Fable 5 <noreply@anthropic.com>

app/api/reports/ar-ledger/xlsx/route.ts

@@ -5,6 +5,7 @@ import {
   reportToWorkbook,
   textColumn,
   currencyColumn,
+  decimalColumn,
   dateColumn,
   integerColumn,
   xlsxFilename,
@@ -111,9 +112,12 @@ export const GET = withRouteContext('report.ar_ledger.xlsx', async (request, { s
           textColumn('Fakturanr'),
           dateColumn('Fakturadatum'),
           dateColumn('Förfallodatum'),
-          currencyColumn('Totalt'),
-          currencyColumn('Betalt'),
-          currencyColumn('Utestående'),
+          // Totalt/Betalt/Utestående are invoice-original currency (see the
+          // Valuta column): the kr-suffixed format is only correct for the
+          // SEK-converted column.
+          decimalColumn('Totalt'),
+          decimalColumn('Betalt'),
+          decimalColumn('Utestående'),
           currencyColumn('Utestående (SEK)'),
           integerColumn('Dagar förfallet'),
           textColumn('Valuta'),