Allow apps to extend the functionality of the extension

[megoth]

Noel De Martin makes an excellent point about allowing apps to make use of the context that is the resource the user is watching, e.g. to show recipe-related functions for webpages about recipes.

I want to consider a way to do this in a secure manner. Given that an app can do a lot in the context of the extension, I think an extra step reminding the user that allowing this feature requires a massive trust in the developer of the app, and possibly allow them to turn off that part of the app's features.

Initial idea for an API is that the app provides a URL for a JS module. It has a default function that provides a request, response API similar to many web APIs.

Example manifest.ttl:

@prefix app: <#> .
@prefix manifest: <https://github.com/megoth/ldo-solid-app-manifest/ontology.ttl#> .
@prefix todo: <https://todo-ldo-megoth.vercel.app/ontology.ttl#> .

</>
    a manifest:Document ;
    manifest:list app:solid-app .

app:solid-app
    a manifest:Manifest ;
    // ...
    manifest:module "https://todo-ldo-megoth.vercel.app/solid-app.js"

Example solid-app.js

default function App(req, res) {
  // do something with req or res
}