Avatar improvements

[techniq]

• [ ] Support passing img which which loads using <img src="..."> and centers/crops based on size
  • Applying A Circular Crop Mask To An Image
• [ ] Support tailwind gradients (mostly just adding examples)
• [ ] Support generating gradient based on name/etc
  • https://github.com/varld/gradient-avatar
• [ ] Support passing multiple to create group/stack (maybe as a separate AvatarGroup component)
  • https://ishadeed.com/article/thinking-about-the-cut-out-effect/
    • https://ishadeed.com/article/css-masking/
  • https://svelte.dev/repl/80ceecce9f234f2490f2b78ffeb2d4d6?version=4.1.2
  • https://mui.com/material-ui/react-avatar/#grouped
  • https://design.procore.com/avatar-stack
  • https://primer.style/design/components/avatar-stack
  • https://codepen.io/landrik/pen/pGVJbq