fix(articles): article ROT/RUT prefill was dead for every dashboard-created article (#1651)

* fix(articles): article ROT/RUT prefill was dead for every dashboard-created article

Follow-up to #1634. The user re-tested and picking a RUT article still left
the line on "Ingen": the article form has always stored the bare kind
('ROT'/'RUT'), while the prefill only recognised Skatteverket work-type codes
(BYGG, STAD, ...). On prod every dashboard-created ROT/RUT article holds the
bare kind, so the fix in #1634 never fired for a real user, and worse, since
the helper returned null for those values, picking such an article CLEARED a
deduction the user had set manually on the row.

- rot-rut-rules: parseArticleHouseworkType() understands both vocabularies
  (code -> kind + arbetstyp; bare ROT/RUT -> kind only), plus
  normalizeHouseworkType()/HOUSEWORK_TYPE_VALUES/workTypeLabel().
- InvoiceEditor.applyArticle: kind-only articles pre-fill the deduction and
  keep a same-kind arbetstyp already chosen on the row; "Spara som artikel"
  round-trips the code or, lacking one, the kind.
- ArticleForm: the ROT/RUT select now offers the real Skatteverket arbetstyper
  in ROT/RUT groups (its own hint always promised "förifyller arbetstyp");
  legacy kind-only values stay selectable as "RUT (arbetstyp ej vald)" so an
  edit never silently drops the flag. Article detail renders "RUT · Städning"
  instead of the raw code.
- API + MCP commit schemas normalize housework_type (case-insensitive code or
  ROT/RUT, '' clears) and reject anything else; the CSV article import
  normalizes the column the same way. Prod holds 178 articles with '0'/'1'
  from a boolean "Rot" column that the keyword detector mapped straight
  through; those now read as no flag everywhere and can no longer be created.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

* fix(articles): review follow-ups on #1651

- InvoiceEditor: switching a row's skattereduktion ROT<->RUT clears an
  arbetstyp from the other list, and Spara som artikel only round-trips a
  work type that belongs to the row's kind (CodeRabbit).
- MCP update_article: null / '' / whitespace now clear housework_type
  (commit drops only undefined keys, so the old undefined mapping made the
  flag un-clearable); create keeps treating them as unset. Tests.
- Article CSV import warns when a non-empty ROT/RUT value is dropped as
  not-an-arbetstyp instead of dropping it silently. Test.
- Hint wording: arbetstyp is pre-filled only when the article carries one.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

---------

Co-authored-by: Jakob Wennberg <311770904+jakobwennberg-oss@users.noreply.github.com>
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>

components/articles/ArticleForm.tsx

@@ -23,6 +23,11 @@ import AccountCombobox from '@/components/bookkeeping/AccountCombobox'
 import { AddAccountDialog } from '@/components/bookkeeping/AddAccountDialog'
 import type { BASAccount, CreateArticleInput } from '@/types'
 import { INVOICE_POSTING_ACCOUNT_REGEX } from '@/lib/invoices/posting-account'
+import {
+  ROT_WORK_TYPES,
+  RUT_WORK_TYPES,
+  normalizeHouseworkType,
+} from '@/lib/invoices/rot-rut-rules'
 
 // A row from the currencies reference table (lib migration
 // 20260630110000_currencies_reference_table.sql).
@@ -202,11 +207,22 @@ export default function ArticleForm({
       revenue_account: initialData?.revenue_account || '',
       cost_price: initialData?.cost_price ?? undefined,
       ean: initialData?.ean || '',
-      housework_type: initialData?.housework_type || '',
+      // Canonical form (work-type code, bare ROT/RUT, or ''): a stray value
+      // from an import must not sit invisibly in the select as "Ingen".
+      housework_type: normalizeHouseworkType(initialData?.housework_type) ?? '',
       notes: initialData?.notes || '',
     },
   })
 
+  // Legacy articles carry only the kind ('ROT'/'RUT'), stored before this
+  // form offered Skatteverket work types. Keep that choice selectable so an
+  // edit never silently drops the flag; the user upgrades it to a real
+  // arbetstyp when they want the invoice row's work type pre-filled too.
+  const legacyHouseworkKind = (() => {
+    const v = normalizeHouseworkType(initialData?.housework_type)
+    return v === 'ROT' || v === 'RUT' ? v : null
+  })()
+
   const type = watch('type')
   const watchedName = watch('name')
   const watchedUnit = watch('unit')
@@ -454,8 +470,27 @@ export default function ArticleForm({
                     onChange={(e) => field.onChange(e.target.value)}
                   >
                     <option value="">{t('housework_none')}</option>
-                    <option value="ROT">{t('housework_rot')}</option>
-                    <option value="RUT">{t('housework_rut')}</option>
+                    {legacyHouseworkKind && (
+                      <option value={legacyHouseworkKind}>
+                        {legacyHouseworkKind === 'ROT'
+                          ? t('housework_legacy_rot')
+                          : t('housework_legacy_rut')}
+                      </option>
+                    )}
+                    <optgroup label={t('housework_rot')}>
+                      {ROT_WORK_TYPES.map((w) => (
+                        <option key={w.code} value={w.code}>
+                          {w.label}
+                        </option>
+                      ))}
+                    </optgroup>
+                    <optgroup label={t('housework_rut')}>
+                      {RUT_WORK_TYPES.map((w) => (
+                        <option key={w.code} value={w.code}>
+                          {w.label}
+                        </option>
+                      ))}
+                    </optgroup>
                   </SettingsSelect>
                 )}
               />