refactor: [shitty claude AI first try] restructure server and user services, add new test cases, and improve error handling

internal/api/auth/repo/auth_repo_test.go

@@ -0,0 +1,34 @@
+package repo
+
+import (
+	"testing"
+
+	"git.logidex.ru/fakz9/logidex-id/internal/api/auth/domain"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestNewAuthRepo(t *testing.T) {
+	// Test with nil client for interface testing
+	// In real tests, you would use a mock or test container
+	repo := NewAuthRepo(nil)
+
+	assert.NotNil(t, repo)
+	assert.Implements(t, (*domain.AuthRepository)(nil), repo)
+}
+
+func TestAuthRepo_Interface(t *testing.T) {
+	// Test that our auth repo implements the domain interface
+	var _ domain.AuthRepository = (*authRepo)(nil)
+
+	// Test constructor returns correct interface
+	repo := NewAuthRepo(nil)
+
+	// Verify interface compliance
+	assert.Implements(t, (*domain.AuthRepository)(nil), repo)
+}
+
+// Note: Actual Redis operations testing requires either:
+// 1. Test containers with real Redis
+// 2. A simpler interface wrapper around Redis
+// 3. A Redis mock library specifically designed for rueidis
+// For now, we focus on interface compliance and constructor behavior