Navigation when validating on "Send inn" button/knapp

### Description

When you are on the Summary/Sammendrag-side and click an Edit-button, you come to the correct page where you want to edit an answer.
This is a good thing, even though you should also have been able to go directly to new pages that are no longer hidden in the "track"/sporvalg.

When you click the "Send" button, you can get quite a lot of validation-messages at the bottom of the page. When you click one of them, you come back to the correct page (like the navigation in summary). But in this case there is no button for:

1. Go back to "Send inn"-page (As there is for the Summary-page)
2. No button for "Go to next error"/"Neste feil"

Both of these buttons would have been very useful.

### Additional Information

_No response_

Start by tracing the validation-message navigation from the Send inn page and compare it with the Summary page's Edit navigation. Done means that after selecting a validation message, users can return to the Send inn page and move to the next error.

Written by the indexing model from the issue text.