fix: wire up auto Business Policy setup trigger on 20403 error

EbayListingTool/Services/EbayListingService.cs

@@ -20,7 +20,8 @@ public class EbayListingService
     private string? _fulfillmentPolicyId;
     private string? _paymentPolicyId;
     private string? _returnPolicyId;
-    private string? _merchantLocationKey;
+    
+    private bool _triedPolicySetup;
 
     public EbayListingService(EbayAuthService auth, EbayCategoryService categoryService)
     {
@@ -35,6 +36,7 @@ public class EbayListingService
         _paymentPolicyId     = null;
         _returnPolicyId      = null;
         _merchantLocationKey = null;
+        _triedPolicySetup    = false;
     }
 
     public async Task<string> PostListingAsync(ListingDraft draft)
@@ -92,8 +94,17 @@ public class EbayListingService
             var json = await res.Content.ReadAsStringAsync();
 
             if (!res.IsSuccessStatusCode)
+            {
+                if (!_triedPolicySetup && json.Contains("20403"))
+                {
+                    _triedPolicySetup = true;
+                    await SetupDefaultBusinessPoliciesAsync(token);
+                    await EnsurePoliciesAndLocationAsync(token, postcode);
+                    return;
+                }
                 throw new HttpRequestException(
                     $"Could not fetch fulfillment policies ({(int)res.StatusCode}): {json}");
+            }
 
             var arr = JObject.Parse(json)["fulfillmentPolicies"] as JArray;
             _fulfillmentPolicyId = arr?.Count > 0
@@ -519,3 +530,5 @@ public class EbayListingService
         return req;
     }
 }
+
+