Upload Custom Artwork for Songs

Description: Let creators upload their own custom cover artwork for songs generated in Songer. Currently, Songer automatically generates the song artwork, but there isn't a way to replace it with a personal image, logo, album cover, or brand artwork. This feature would allow users to: Upload a JPG or PNG as their song artwork. Replace the AI-generated image at any time. Display the custom artwork when sharing Songer links. Use personal branding, artist logos, or album covers. Present songs more professionally when sharing or promoting them. This would be especially valuable for artists, musicians, businesses, ministries, and content creators who want consistent branding across their releases.