LP1865898 Missing pieces mult-scan work flow improvements

LP1865898 Missing pieces mult-scan work flow improvements

After an item is marked as missing pieces, select/focus the barcode
input so another item can easily be marked as missing pieces without
having to manually clear the form / reload the page.

Tweaks the "Cancel" button to use the text "Reset Form" once the current
item has been processed, since it can no longer be canceled, but the
form can be forceably cleared if desired.

Signed-off-by: Bill Erickson <berickxx@gmail.com>
Signed-off-by: Mike Risher <mrisher@catalyte.io>
Signed-off-by: Galen Charlton <gmc@equinoxinitiative.org>