From the rewards calculation output, build the merkle tree

Check out the logic and database schema at https://www.notion.so/Minimum-Token-Utility-Rewards-Spec-1f2dfc9427de8027951ec3645bf02fc5?d=1f8dfc9427de80c59b80001cc7cfd01e#1f2dfc9427de8019b7c6fa1f3e363ded