Allow embedding Ameliorate in other sites

[keyserj]

Describe your issue

Some related apps may benefit from including Ameliorate in their experience, enabling precise discussion of some problems related to their app. But in these cases, those apps probably prefer not to have their users leave the flow/context of their app.

Example: Digital Democracy Project has a mobile app that embeds Kialo to provide bill summaries that citizens can engage with. Their website embeds Kialo too (if you click Show Kialo Discussion on a bill's page).

Solution you'd like

Allow other apps/sites to embed Ameliorate.

Notes:

• seems like this is already doable - try replacing any of the iframes at https://codepen.io/leemark/pen/ozyWbv with the URL https://ameliorate.app/examples/detailed-cars-going-too-fast
  • there should probably be a ?embed param or something to turn off everything in the App Header (left/right corners) except for prev/next/undo/redo buttons, and probably "log in"

Alternatives you've considered

No response

Additional context

Want to remove similar things from the app header for #603 too (though that actually wants "log in" removed as well)

Technical ideas and questions

thoughts:

• probably embed via iframe
• seems like URL navigation can be a security issue? but URLs can just open in a new tab, that's fine.
• each iframe is a new browsing context so maybe test for performance concerns

questions

• can the embedded site still use its cookies/localstorage the same as when not embedded?
  • seems like the ameliorate.app localstorage is separate from [different-top-level-domain]/ameliorate.app localstorage. so embedding the playground results in persistence based on the host site. this seems fine
• does iframe function differently from webview, if this is used in a native mobile app?