Allow "Copy from archive", but stop instantiation from direct URL

### Description

We (SSB) usually have prefill sent with a subscription. In order to allow the user to create a copy from archive, we need to let them have rights that lets them "instatiate" the app. We have to use "autoCreate": false because of how the prefill is sent. This causes problems when a user tries to start an app directly from an URL. There is no data model, and therefore the app will be left hanging until it crashes in a "not-so-pretty" way.

We need to be able to either have some way to allow copy from archive to work for a user without being allowed to instantiate, or be able to make a rule on instantiation that can give the user some kind of useful message like "You have to open the schema from your Altinn inbox, or create a new copy from your archive".

### Additional Information

See Slack discussion here https://altinn.slack.com/archives/C02EVE4RU82/p1725622983665109

Start by tracing how autoCreate=false, archive copying, and direct-URL instantiation are handled in the app-lib-dotnet entry points; the issue names no files or tests. Done should mean either archive copying works without instantiation rights, or direct access produces a useful message directing the user to their Altinn inbox or archive.

Written by the indexing model from the issue text.