fix

docs/category-formulas.md

@@ -78,6 +78,47 @@ go run ./cmd/formula-e2e -new-tenant -llm-base http://127.0.0.1:18767/v1
 `-llm-base` pins the provider for the run; without it the harness uses whatever
 `platformsettings.ResolveOpenAI` returns (admin DB setting first, then env).
 
+## What Review compares
+
+Review shows Original vs Enriched for name, description, category, attributes and
+SEO meta. Each "Original" must come from a source the pipeline never writes, which
+is less obvious than it sounds:
+
+| field | Original comes from | trap |
+|---|---|---|
+| name / description | `original_name` / `original_description` | `name`/`description` from the API are display-preferred and resolve to the ENRICHED copy |
+| category | `feed_category` | `mapped_data.category` is written back by the pipeline; `category_source` says who chose it |
+| attributes | `mapped_data.specifications` (feed specs) | `processed_products.attributes` is written to the same value as `processed_attributes` |
+| | | EPREL writes one fact under several names — `product-attributes.ts` folds the aliases so it is listed once |
+| SEO meta | `mapped_data.meta_*` | most feeds have none, so Enriched shows as **Added** |
+
+Attributes are grouped **Added / Changed / Unchanged**, with unchanged collapsed —
+a review should lead with what the run actually did. Alias keys are folded into one
+row: enrichment stores `eprel_pdf` and `eprel_pdf_url`, `energy_class` and
+`eprel_energy_class`, which otherwise listed the same fact two or three times.
+Folding needs a related name AND an identical value, so width and height are never
+merged just because they match (`$lib/attribute-diff`, unit-tested).
+
+The product detail endpoint deliberately does **not** apply the SEO-meta omit rule.
+That rule keeps meta out of list views for cohorts that do not sell on it, but the
+detail payload feeds review, and meta the pipeline actually generated has to be
+reviewable — the panel hides the block itself when both sides are empty.
+
+Anything with no Original is labelled **Added** and shown as "not in feed", not
+"Matched" — saying Matched about a field the supplier never sent reads as if the
+feed had one.
+
+Two things behave this way by design, not by accident:
+
+- **A1 Slovenija and Platform Demo do not GENERATE SEO meta**
+  (`processing.CompanyOmitsSEOMetaID`). Meta already stored on their rows is still
+  shown — the read path only hides empty values, so Review and Content display what
+  the AI actually produced.
+- **Rows processed before `category_source` existed** cannot say whether their
+  `mapped_data.category` came from the feed or from an earlier AI run, so Review
+  still treats it as feed-supplied. Reprocessing the product records the real
+  provenance.
+
 ## Low-confidence categorisation fails the product
 
 The categorize model always answers with *some* id from the list, so a reply like