Method Upsert

internal/nodes/memory.go:20–25

(node Node)

}

func (s *MemoryStore) Upsert(node Node) (Node, error) {
	s.mu.Lock()
	defer s.mu.Unlock()
	s.nodes[node.ID] = node
	return node, nil
}

func (s *MemoryStore) Delete(id string) error {
	s.mu.Lock()