Content Bounty: Solana NFT Deal Score

In this bounty, answer the following questions: 1. What are rarity tools? 2. What howrare.is and moonrank? 3. How MoonRank works? 4. How HowRare.is works? 5. What does NFT deal do differently than other rarity tools like `howrare.is` and `moonrank` for evaluating Solana NFTs? 6. What are the advantages of using a machine learning model compared to strict rarity tools? 7. how should use NFT Deal score with example.