Sacar pestaña Test del admin

- Borrado public/components/test-panel.js + su nav button + su rango de
  router + sus rutas /test/products-with-stock y /test/order.
- Borrados handleGetProductsWithStock + handleCreateTestOrder y los
  api wrappers getProductsWithStock + createTestOrder. Ya no se usan en
  ningún flujo: pruebas de bot se hacen vía simulator.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

public/lib/api.js

@@ -234,18 +234,6 @@ export const api = {
     return this.listOrders({ page: 1, limit });
   },
 
-  async getProductsWithStock() {
-    return fetch("/test/products-with-stock").then(r => r.json());
-  },
-
-  async createTestOrder({ basket, address, wa_chat_id }) {
-    return fetch("/test/order", {
-      method: "POST",
-      headers: { "Content-Type": "application/json" },
-      body: JSON.stringify({ basket, address, wa_chat_id }),
-    }).then(r => r.json());
-  },
-
   // --- Prompts CRUD ---
   async prompts() {
     return fetch("/prompts").then(r => r.json());