What problem does this address?

Currently, adding additional options to the Add media or Replace toolbar dropdown from the Image and Cover blocks is not possible. Instead, this is only possible in the block content.

What is your proposed solution?

Add a hook into this toolbar dropdown menu, so plugins can add their options there.

There's a related feature request regarding this, too: #34663

Context

In WordPress.com, some additional options are added, like importing an image from Google Photos, among others:

It would be great to have this hook to be able to add more options directly in the Add media or Replace toolbar button.