Create order

Create a new order with variant-specific items

Creates an order by:

1. Validating variant availability for each item
2. Creating order record in V1 orders table
3. Creating market_orders entries (V1 compatibility)
4. Creating order_market_items_v2 entries with variant tracking
5. Snapshotting variant prices at purchase time
6. Allocating stock from variant-specific lots
7. Notifying seller of new order

Uses database transaction for atomicity to ensure all-or-nothing behavior. Stock allocation uses listing_item_lots directly (V2).

Requirements:

• 25.1: POST /api/v2/orders endpoint
• 25.2: Accept array of items with listing_id, variant_id, quantity
• 25.3: Validate variant availability before order creation
• 25.4: Use variant-specific pricing in order calculations
• 25.5: Allocate stock from correct variant's stock lots
• 25.6: Use database transaction for atomicity
• 25.7: Snapshot variant prices at time of order creation
• 25.8: Prevent ordering unavailable variants with descriptive error
• 25.9: Create order_market_items_v2 entries for each item
• 25.10: Return order_id and order details on success
• 25.11: Notify seller of new order
• 25.12: Log order creation to Audit_Trail