Give veKANA usage

VeKANA has always lacked a source of income, so few people are willing to lock KANA. We need to give vetoken a larger and longer-term income capacity than other vaults to maintain the $KANA price, which is conducive to the development of the project. So I propose that vetoken holders will be able to draw 10% of the income from each vault, and the earned $kana will be displayed on the DAO page.