Add field for image description

[jcoyne]

Why was this change made? 🤔

This helps support accessibility and AI feature extraction for indexing

[edsu]

Is there a reason why this isn't added a level up next to label?

[jcoyne]

@edsu because it's only on images and it's for presentation.

[justinlittman]

How is this different than the file label field?

[andrewjbtw]

1. Won't alt-text be needed on other types of content?
2. How will someone edit this field? I think it's a good idea to add fields that users will need to edit only in conjunction with some way for a user to edit them.

[jcoyne]

How is this different than the file label field?

The label field is user provided text, but it is not intended to be used as alt text.

Won't alt-text be needed on other types of content?

The alt attribute is only supported on images (also <area> and <input> but we don't use these to present SDR objects)

How will someone edit this field? I think it's a good idea to add fields that users will need to edit only in conjunction with some way for a user to edit them.

Currently undetermined.