Lying in the sun stands for rest, warmth and soaking up attention or good energy. Tradition reads it as a pause you allow yourself, and as a wish to be seen.
Has this come up in your dreams before? What was going on in your life then?
My Cosmic Code has a private dream journal. Write a dream down and the app picks out the symbols in it, shows what dream books say about them and, over time, which words recur across your entries. The journal is stored on your device only.