There was a feature request that got implemented few days ago for the image search https://kagifeedback.org/d/1704-allow-ctrlv-for-image-search-on-kagi-if-image-in-clipboard
Can we get the exact same UX for the assistant upload?
Basically the same reasons as the image search one, it's way easier to upload files this way if you already have e.g. screenshots in your clipboard
