Add an embed page that is focused on compactly representing the neuron information

[esbenkc]

This will enable anyone to embed a link to a specific neuron on their web pages and get a pretty-ish representation of that neuron's activation.

[albertsgarde]

This actually seems to be pretty easy to do using the Rollup plugin for Svelte.

• Bare essentials guide: https://codeandlife.com/2021/03/06/easy-to-embed-svelte-components/
• Official guide to the Rollup plugin: https://rollupjs.org/introduction/