[FEATURE] Catalog migration with sync mode (catalog.* API)

Summary / Резюме

• EN: Implement catalog migration command with synchronization mode
• RU: Реализовать команду миграции каталога с режимом синхронизации

Requirements / Требования

Entities / Сущности

| Entity | API | Count |
|--------|-----|-------|
| Sections | catalog.section.* | 93 |
| Properties | catalog.productProperty.* | 4 |
| Products | catalog.product.* | 529 |
| Prices | catalog.price.* | 529 |

Features / Функции

1. SYNC mode: ADD / UPDATE / SKIP logic
2. XML_ID mapping: MIG_B1_{SOURCE_ID}
3. User mapping: CREATED_BY, MODIFIED_BY → B2 users
4. Hierarchy: Sections with parent-child relations
5. Batch processing: 50 items per batch

Command / Команда

php bin/migrator migrate --entity=catalog

Technical Notes

• Uses NEW catalog.* API (not deprecated crm.product.*)
• Prices set via separate catalog.price.* methods
• Images via base64 in fileData

Acceptance Criteria

• [ ] All 93 sections migrated with hierarchy
• [ ] All 4 properties created
• [ ] All 529 products synced (ADD/UPDATE/SKIP)
• [ ] All prices set correctly
• [ ] User mapping applied (CREATED_BY, MODIFIED_BY)
• [ ] Re-run = only UPDATE changed, SKIP unchanged