[Cart] Add high-level CLI workflows

[KeeganEad]

Summary

• add Cart listing create, cancel, cancel-root, and invalidate-nonce commands
• add Cart checkout with repeatable listing digests, preview mode, consent-aware approvals, and SDK bundle verification
• pin the independent-Variant rare-sdk PR docs: update docs for offers, listings, currencies; bump to 0.4.1 #14 head
• add deterministic built-CLI coverage plus live Rare API and Sepolia coverage
• deploy and index fresh collections/tokens through the public Variant catalog without authenticated Product/SKU fixture writes
• verify settlement entitlements and OrderLineSettled receipts against API preparations
• add live ERC-1155 transfer and mint-to coverage, plus isolated ERC-721 mint-to coverage
• add a maximum-size live Cart checkout under the current adjustment model: 9 listing items, 19 order lines, and 9 fulfillment actions
• add multi-seller USDC checkout coverage across ETH and RARE settlement currencies
• add a secondary-sale ERC-2981 royalty fixture with distinct creator/royalty recipient, secondary seller, and buyer; assert prepared seller proceeds, royalty lines, exact recipient deltas, receipt values, and final ownership
• make live wallet selection capable of reserving a buyer with sufficient token balance and retry transient read-only catalog polling

Stack

Depends on #135.

SDK dependency: superrare/rare-sdk#14.

Validation

• npm test: 29 files passed, 173 tests passed, 2 skipped
• npm run typecheck (via npm test)
• npm run test:typecheck (via npm test)
• npm run lint -- --no-cache
• git diff --check
• live Sepolia ERC1155_TRANSFER (fulfillment kind 3): passed
• live Sepolia ERC1155_MINT_TO (fulfillment kind 5): passed
• live Sepolia maximum checkout (9 listings / 19 order lines / 9 actions): passed
• live Sepolia secondary ERC-2981 royalty checkout: passed (1 test in 85.81 seconds)

Live integration status

The successful live runs exercised public catalog lookup, Listing Root publication, API checkout preparation, signed purchase execution, exact ERC-1155 balance changes, and Cart settlement/fulfillment receipt events.

After the Rare API deployment completed, the isolated secondary royalty fixture passed end to end: fresh deployment, mint-to-secondary ownership, nonzero ERC-2981 creator quote, explicit Cart approval, Listing Root publication, checkout preparation, exact 90% seller proceeds and 10% creator royalty lines, signed purchase execution, exact recipient ETH balance deltas, exact OrderLineSettled receipt values, and final buyer ownership.

The full-suite rerun also exposed a sequencing incompatibility: Rare API now rejects /v1/cart/listings/preview with HTTP 409 when Cart does not already have NFT approval. The CLI/SDK listing flow relies on preview to determine required approvals before --yes performs them, so fresh unapproved ERC-721/ERC-1155 listings cannot currently reach auto-approval. The royalty fixture explicitly preapproves Cart as a setup precondition and therefore verifies the downstream royalty behavior independently.

ERC721_MINT_TO remains independently covered by the live suite but the latest run timed out waiting for a catalog SKU for the seeded lazy ERC-721 token. Quote-change-during-checkout coverage remains owned by Rare API because the live CLI fixture has no safe supported mechanism to mutate the royalty quote mid-order.