fix(api): remove unused listOrdersByConsumer helper

The function performed client-side filtering on top of listOrders
but was never called by any page. listPlayersByShop is kept as-is
since the backend has no dedicated shop players endpoint.

tests/orders-api.test.ts

@@ -21,6 +21,13 @@ describe("lib/api/orders", () => {
         quantity: 1,
       })
 
+      expect(fetch).toHaveBeenCalledWith(
+        expect.any(String),
+        expect.objectContaining({
+          body: JSON.stringify({ playerId: 1005, serviceId: 5001, quantity: 1 }),
+        }),
+      )
+
       expect(res).toEqual({
         decision: {
           ok: false,