ChooseSolidAccount

Opens the system account chooser over Android Solid Services' accounts — every signed-in WebID appears there, with "Add account" routing into Android Solid Services' own sign-in.

Returns the chosen WebID, or null when the user backs out. Two properties come from the OS itself:

• on Android 8+ your app cannot even see these accounts until the user picks one here; the pick is what grants your app visibility of exactly that account, mediated by the system;

• picking is identification, not authorization — it does not grant pod access. Follow up with AuthorizeWithSolid, where the user confirms what your app may do as that WebID.

AuthorizeWithSolid alone already covers the common case (its picker both selects and grants); reach for this contract when you want the platform-native chooser, or its "Add account" entry point.

private val choose = registerForActivityResult(ChooseSolidAccount()) { webId ->
    if (webId != null) authorize.launch(Unit)
}
choose.launch(Unit)