Recognize B-prefix location codes as temp storage shelves. Add purple
color scheme, conflict detection for temp_stored status, and updated
submit/dialog logic for temp storage target handling.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
In multi-code shelving mode, if the user has scanned zongpai numbers
but hasn't scanned any shelf yet, scanning the first shelf should not
trigger the "switch shelf" warning dialog since there is no existing
shelf to switch from.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>