feat(api): add auth permission to all api endpoint

app/apps/api/serializers/currencies.py

@@ -1,8 +1,12 @@
 from rest_framework import serializers
+from rest_framework.permissions import IsAuthenticated
+
 from apps.currencies.models import Currency, ExchangeRate
 
 
 class CurrencySerializer(serializers.ModelSerializer):
+    permission_classes = [IsAuthenticated]
+
     class Meta:
         model = Currency
         fields = "__all__"
@@ -24,6 +28,8 @@ class ExchangeRateSerializer(serializers.ModelSerializer):
         queryset=Currency.objects.all(), source="to_currency", write_only=True
     )
 
+    permission_classes = [IsAuthenticated]
+
     class Meta:
         model = ExchangeRate
         fields = "__all__"