Function edit 

pub fn edit(
    path: &Path,
    profile: &str,
    edits: &Edits<'_>,
) -> Result<String, EditError>

Change an existing profile in place, optionally renaming it.

Its own function rather than a mode of upsert, and for the same reason set_default is: editing a profile is a local edit to a file the user owns, and making them log in again — token, verification and all — to fix a typo in an organisation id would be theatre.

A rename moves the table rather than copying its fields, so [profiles.x.display] and anything hand-written inside it travel with it, and default_profile is carried across because a default naming a profile that no longer exists breaks every later command.