Added logger and tests

lib/currency/riksbanken.ts

@@ -1,5 +1,8 @@
+import { createLogger } from '@/lib/logger'
 import type { Currency, ExchangeRate } from '@/types'
 
+const log = createLogger('riksbanken')
+
 /**
  * Fetch exchange rates from Riksbanken API
  * Uses their public API for daily exchange rates
@@ -31,7 +34,7 @@ export async function fetchExchangeRate(
 
   const seriesId = seriesIds[currency]
   if (!seriesId) {
-    console.error(`Unknown currency: ${currency}`)
+    log.error(`Unknown currency: ${currency}`)
     return null
   }
 
@@ -84,7 +87,7 @@ export async function fetchExchangeRate(
 
     return null
   } catch (error) {
-    console.error('Error fetching exchange rate:', error)
+    log.error('Error fetching exchange rate:', error)
     // Return fallback rates for development/testing
     return getFallbackRate(currency)
   }