Bulk create listings

Create many listings in one request with per-record success tracking.

Use this endpoint for high-volume listing ingestion from seller tools or migration flows.

Request limits and validation:

• Accepts up to 200 listing payloads per call.
• Each listing uses the same schema and validation rules as single listing creation.
• Optional reference metadata is accepted per listing and normalized the same way as single-create.
• Duplicate URNs in the request are allowed but each array entry is still processed independently.

Processing model:

• Listings are processed one by one; one failure does not stop other records.
• Missing items, validation failures, or persistence errors are captured per listing.
• Empty-string reference values are treated as a clear request (null in storage).
• The response always returns two URN arrays: successful and failed.

Seller and listing rules:

• Caller must be an active seller.
• Item URNs must exist in the catalog index to create a listing.
• Listing validity follows the same photo requirement logic as single-create:
  • price >= 2000 or grading metadata requires at least one attachment to become valid.

Side effects:

• Emits LISTING_CREATED webhook events for each successfully created listing.
• Invalidates seller stats cache tags as successful records are written.
• Writes per-listing analytics events.