Add editable article prices with gross input and staffel tiers.

Wire PUT /prices, de-DE formatting, tax/staffel pills, and keep the category list cache in sync after photo/price updates.

src/api/index.js

@@ -221,6 +221,19 @@ export const article = {
       body: { fullHashes },
     });
   },
+
+  /**
+   * PUT /api/article/:sku/prices
+   * Body: { prices: [{ price (net), tax (rate), minmultiplier? }] }
+   * Replace-all POS customer group prices. Empty prices clears all POS prices.
+   * → 200 { article } (same shape as GET by SKU)
+   */
+  setPrices(sku, prices) {
+    return http(`/api/article/${encodeURIComponent(sku)}/prices`, {
+      method: 'PUT',
+      body: { prices },
+    });
+  },
 };
 
 /**