Add article pack units with Redux-cached company unit list.

Edit amount/unit on the price tile (pc×1 = no pack unit), manage units in a dialog, and keep the default pc unit non-deletable.

src/api/index.js

@@ -167,8 +167,9 @@ export const article = {
 
   /**
    * PATCH /api/article/:sku
-   * Body: partial fields, e.g. { name }
-   * → 200 { article }
+   * Body: at least one of { name, unitamount, unitSi }
+   * unitSi must exist for selected company → 404 Unit not found
+   * → 200 { article } (same detail shape as GET)
    */
   update(sku, body) {
     return http(`/api/article/${encodeURIComponent(sku)}`, {
@@ -250,6 +251,35 @@ export const thumb = {
   },
 };
 
+/**
+ * Company-scoped units (selectedCompanyId from session).
+ * Shape: { si, basesi, basesifactor, symbol, name }
+ */
+export const unit = {
+  /** GET /api/unit → { units: [...] } · 400 No company selected */
+  list() {
+    return http('/api/unit');
+  },
+
+  /**
+   * PUT /api/unit
+   * Body: { si, basesi, basesifactor, symbol, name }
+   * → 200 { unit }
+   */
+  upsert(body) {
+    return http('/api/unit', { method: 'PUT', body });
+  },
+
+  /**
+   * DELETE /api/unit?si=… → 204
+   * 409 Unit in use
+   */
+  delete(si) {
+    const params = new URLSearchParams({ si });
+    return http(`/api/unit?${params}`, { method: 'DELETE' });
+  },
+};
+
 export const category = {
   /** GET /api/category/tree → { languageId, tree, articles } (company from session) */
   getTree() {
@@ -372,4 +402,4 @@ export const auth = {
   },
 };
 
-export default { auth, article, category, company, thumb };
+export default { auth, article, category, company, thumb, unit };