Form Block: add form settings to block toolbar

The Form block toolbar is currently empty. It would be nice to offer quick access to the form settings (email address, ...) from the block toolbar


The issue names no file, test, or entry point. Start by locating the Form block toolbar implementation and the existing form-settings controls; verify how toolbar actions are registered in the editor. Done means the toolbar exposes quick access to the form settings, including the email address setting, and those controls work from the block.

Written by the indexing model from the issue text.