Create accessory_page.dart with step-by-step form for registering
product accessories: paichan_no query, work order selection, zongpai_no
auto-fill, accessory type selector (preset + custom), quantity input,
location code (scanner + manual), and submit. Includes registered
accessories list with edit/delete actions and boxed-item indicators.
Integrates with ScannerService, FeedbackService, and StatusBar.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
12cab16888