# Decision: article generation reads lot_category from the component universe, not one pricelist

**Date:** 2026-09-01
**Status:** active

## Context

`internal/article/generator.go` classifies each cart LOT into an article segment
(CPU / MEM / GPU / DISK / NET / PSU) by its `lot_category`. That category was
resolved by `ResolveLotCategories` → `GetLocalLotCategoriesByServerPricelistID`,
which queries exactly **one** pricelist — the configuration's pinned
`pricelist_id` (an `estimate` pricelist). A segment builder skips any LOT whose
category is unknown, so a LOT absent from that one pricelist vanished from the
article with no warning.

`GPU_NV_RTX_PRO_6000D_SERVER_84GB_PCIE` exposed this: it exists only in `world`
pricelists (where it correctly carries `lot_category = GPU`) and in no `estimate`
pricelist. It was priced (world fallback), exported, and shown in the cart, but
dropped from the article.

This is the same class of bug as
[2026-07-24-component-universe-world-union.md](2026-07-24-component-universe-world-union.md):
the cart's LOT set is `world` ∪ `estimate`, and no read path may silently drop a
LOT that only lives in `world`. Article generation was the one component-reading
path still scoped to a single pricelist.

Deriving the category from the `lot_name` prefix was rejected — it is forbidden by
the pricelist-contract rules (`02-architecture.md`, `bible/rules/patterns/`):
category comes only from real synced pricelist columns.

## Decision

`ResolveLotCategories(local, lotNames)` now calls
`LocalDB.GetLocalComponentCategoriesByLotNames`, which reads the component universe
(`componentUniverse()` — latest active `world` ∪ `estimate`, estimate wins a
collision). The server-pricelist parameter is gone.

- `article.BuildOptions` no longer has `ServerPricelist`.
- `POST /api/configs/preview-article` and the create/update paths still accept
  `pricelist_id` but ignore it for article purposes.
- The `lot_name`-token parsing inside a segment (CPU model, memory size, GPU model,
  disk capacity, port speed, wattage) still parses the token from the `lot_name` —
  that produces the article text, it does not categorize. One parser bug was fixed
  alongside: `parseGPUModel` required the model-number token to be all digits
  (`isNumeric`), so `RTX_PRO_6000D` lost its `D` and collapsed to `RTX_84GB` —
  indistinguishable from a real `RTX` card and different from its sibling
  `RTX_PRO_6000` → `RTX6000_96GB`. It now accepts a digit-first alphanumeric token
  (`isModelNumber`), giving `RTX6000D_84GB`.

## Consequences

- A world-only LOT lands in the article with its real category. Article generation
  no longer depends on which pricelist a LOT was added to.
- The article can shift if the latest active `world`/`estimate` pricelist
  recategorizes a LOT — acceptable, and consistent with how the configurator's
  category tabs already behave.
- `GetLocalLotCategoriesByServerPricelistID` still exists and is still used by
  `services/rental.go` and `services/export.go`. Those paths have the same
  single-pricelist blind spot for world-only LOTs; migrating them is out of scope
  here but should follow the same direction.
- Covered by `TestResolveLotCategories_WorldOnlyLot` in
  `internal/article/categories_test.go`.