Re-Add Variations Summary

[Oakes6]

Restore VariationSummary resource & fill in entity gaps surfaced by the Creators API SDK

Why

The Creators API migration mistakenly removed EnableVariationSummary() — The official Amazon SDK (get_variations_resource.py) explicitly enumerates:

• variationSummary.price.highestPrice
• variationSummary.price.lowestPrice
• variationSummary.variationDimension

Because we never requested those resources, the response's variationSummary block was always empty — pageCount, variationCount, the price range, and the variation dimensions all came back nil even though the entity already had fields for them.

While auditing the rest of the SDK I also found a handful of smaller decode gaps that this PR cleans up at the same time.

Changes

Resource enable + plumbing

query/resources.go — re-added resourceVariationSummary with the three lowerCamelCase strings above.

query/query.go — Query.VariationSummary() is no longer a no-op; it sets the resource flag. The // Deprecated: comment is replaced with a description of the response block this resource populates.

Entity field gaps

entity/entity.go — five fixes uncovered while cross-checking each Creators API model against entity.Item:

Gap	Fix
Images.Primary.HiRes and Images.Variants[].HiRes missing	Added HiRes *Image \json:"hiRes,omitempty"`. The Creators API uses hiResin responses even though the resource enum isimages.primary.highRes` — quirk in the API itself, not a typo on our side.
VariationDimension.Locale missing	Added Locale string.
BrowseNodeInfo.BrowseNodes[].WebsiteSalesRank.Id missing	Added Id string \json:"id,omitempty"``.
Top-level BrowseNodesResult.BrowseNodes[].SalesRank missing	Added SalesRank *int.
OffersV2.Listings[].ViolateMAP decoded the wrong key	Renamed to ViolatesMAP with explicit \json:"violatesMAP,omitempty"`tag. The previous field was a typo carried over from PA-API v5; the Creators API actually returnsviolatesMAP` (with the "s").

Tests

entity/entity_test.go (new) — focused decode tests asserting all of the above end-to-end:

• pageCount, variationCount, price.highestPrice/lowestPrice, variationDimensions[].locale populate from a Creators API GetVariations payload.
• images.primary.hiRes, isBuyBoxWinner, violatesMAP populate on items / V2 listings.
• Top-level browseNodes[].salesRank and websiteSalesRank.id populate.
• Regression check that unknown JSON keys don't break decode (so future API additions are forward-compatible).

query/query_test.go, query/getvariations_test.go — EnableVariationSummary() expectation flipped from {} to the three resource strings.

Docs

README.md — removed the now-incorrect "no-op (resource is not exposed)" row for EnableVariationSummary from the legacy-fields table.

Verification

• go build ./... clean.
• go vet ./... clean.
• go test -count=1 -race ./... passes (root, entity, query).

Migration impact

• No behavior change required for callers already invoking q.EnableVariationSummary() — they were getting silent nils, now they get populated data.
• OffersV2.Listings[].ViolateMAP field rename to ViolatesMAP is a minor source-level break for anyone reading that field directly. Trade-off: the previous name never decoded the new API's payload anyway, so callers reading it were always seeing false regardless of the actual offer status. Renaming is the correct fix.

Risk / rollback

Low. Reverting puts EnableVariationSummary() back to a no-op (the bug we're fixing) and restores the broken ViolateMAP decode, so rollback is only useful if the new resource string somehow misbehaves at the API — which is verifiable with a single live GetVariations call. Forward-fix is preferable.

[Oakes6]

@spiegel-im-spiegel patching latest release to include neglected entity fields

[spiegel-im-spiegel]

Thanks again for the contribution. Based on the latest review, here is the proposed split plan.

Important update: we do not need to keep ViolateMAP for backward compatibility. It appears to be a typo from older docs, so we should standardize on ViolatesMAP only.

Proposed split:

1. PR A: safe migration fixes (merge first)

• Restore VariationSummary resource wiring and tests.
• Keep additive entity decode fixes that align with current Creators API payloads.
• Keep itemResults decoding compatibility.
• Use ViolatesMAP only (drop ViolateMAP).

2. PR B: behavior and shape adjustments (review separately)

• Any field removals or contract-tightening changes.
• Any resource-scope reductions (for example image resource contractions).
• Any test rewrites that change expected behavior rather than validating migration compatibility.

This keeps PR A low-risk and easy to validate, while giving PR B focused review with explicit migration notes and evidence.

[spiegel-im-spiegel]

I opened PR #50 as the PR-A extraction derived from this PR (#49): #50

It contains only the low-risk migration-compatible subset so we can merge safe fixes first, while keeping higher-risk behavior/shape changes for a separate PR-B review.

[spiegel-im-spiegel]

Update: the safe subset has now been merged via PR #50.

• Merged PR: Safe Creators API migration fixes (derived from #49) #50
• Scope merged first: low-risk migration-compatible fixes (PR-A)

We can continue reviewing the remaining higher-risk behavior/shape changes separately as PR-B.

[Oakes6]

@spiegel-im-spiegel Sounds good! Will reopen a PR for those changes.