Display invalid data and allow users to correct before submission

In https://github.com/getodk/web-forms/issues/691 we decided that codecs should not throw errors when given invalid data, for example, integers greater than max int. The solution we landed on was to null out the value but this means users have no indication of what the value used to be.

The invalid data often happens when editing a submission that was sent from another client which has different tolerances for that data type. It could also theoretically happen due to directly editing the xml, or through bind calculations.

### User story

- As a data entry user I want to see the invalid value when editing a form so that I can correct the data before submission.

Start by reading issue 691 and tracing how codecs handle invalid values during submission editing. Inspect the form-editing path and the handling of values from other clients, XML edits, and bind calculations; done means users can see each invalid value and correct it before submission.

Written by the indexing model from the issue text.