Reapply "feat(loyalty): EnakPoint & EnakCoin" (#32)

This reverts commit 4e24f9bbb0.

internal/entities/campaign_test.go

@@ -0,0 +1,18 @@
+package entities
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestNormalizeCampaignTypesMapsLegacyTokensToCoins(t *testing.T) {
+	assert.Equal(t, CampaignTypeCoins, NormalizeCampaignType("TOKENS"))
+	assert.Equal(t, CampaignTypeCoins, NormalizeCampaignType("COINS"))
+	assert.Equal(t, CampaignTypePoints, NormalizeCampaignType("POINTS"))
+	assert.Equal(t, CampaignType(""), NormalizeCampaignType(""), "an empty filter stays empty")
+
+	assert.Equal(t, CampaignRewardTypeCoins, NormalizeCampaignRewardType("TOKENS"))
+	assert.Equal(t, CampaignRewardTypeReward, NormalizeCampaignRewardType("REWARD"))
+	assert.Equal(t, CampaignRewardType(""), NormalizeCampaignRewardType(""))
+}