Sort field names by title and improve field identification if possible

[bobbingwide]

It would be nice if the field names could be sorted by field name, as in the screenshot below.

It would also be nice if the field names could be improved to indicate the field group to which the field is associated.
This is in addition to the Post types which are already shown.

Once this has been done it may no longer be necessary to display the raw field name and key value,
which is currently included in the select list when SCRIPT_DEBUG is true.

In this example the first Range field is from the Clone group that's only applicable to CPT Block examples. For this particuar post and the block's context it's the second field that we need to pick.

[bobbingwide]

In this screenshot the select list now contains the title of the group to which each field is associated.
This information should help the user decide which field to choose.