chore(init): 初始化解忧商行项目并完成 Phase 0 基座

backend/internal/modules/adminaudit/service.go

@@ -0,0 +1,23 @@
+package adminaudit
+
+import (
+	"context"
+	"errors"
+)
+
+var ErrDependencyUnavailable = errors.New("dependency unavailable")
+
+type Service struct {
+	repo *Repository
+}
+
+func NewService(repo *Repository) *Service {
+	return &Service{repo: repo}
+}
+
+func (s *Service) List(ctx context.Context, query Query) (*PaginatedResult, error) {
+	if s.repo == nil {
+		return nil, ErrDependencyUnavailable
+	}
+	return s.repo.List(ctx, query)
+}