Improve Shopify sync error logging

Log clear hint for 403 (IP whitelist), 401, 429, 5xx.
Commands exit with failure and print error when API returns no data.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

app/Console/Commands/ShopifyMap.php

@@ -16,6 +16,11 @@ class ShopifyMap extends Command
         $dryRun = $this->option('dry-run');
         $variants = $shopify->getAllVariants();
 
+        if (empty($variants)) {
+            $this->error('Keine Varianten von Shopify erhalten — API-Aufruf fehlgeschlagen (Details im Log).');
+            return self::FAILURE;
+        }
+
         $this->info('Shopify-Varianten geladen: ' . count($variants));
 
         $mapped = 0;

app/Console/Commands/ShopifySync.php

@@ -18,6 +18,11 @@ class ShopifySync extends Command
         $dryRun = $this->option('dry-run');
         $variants = $shopify->getAllVariants();
 
+        if (empty($variants)) {
+            $this->error('Keine Varianten von Shopify erhalten — API-Aufruf fehlgeschlagen (Details im Log).');
+            return self::FAILURE;
+        }
+
         $added   = 0;
         $removed = 0;
         $inSync  = 0;

app/Services/ShopifyService.php

@@ -31,7 +31,19 @@ class ShopifyService
             $response = Http::withHeader('X-Shopify-Access-Token', $this->token)->get($url);
 
             if ($response->failed()) {
-                Log::error('Shopify API error', ['status' => $response->status(), 'body' => $response->body()]);
+                $status = $response->status();
+                $hint   = match (true) {
+                    $status === 401 => 'Access Token ungültig oder fehlt',
+                    $status === 403 => 'IP-Whitelist: VPS-IP ist in Shopify nicht freigeschalten',
+                    $status === 429 => 'Rate Limit überschritten',
+                    $status >= 500  => 'Shopify-seitiger Fehler',
+                    default         => 'Unbekannter Fehler',
+                };
+                Log::error("Shopify Sync fehlgeschlagen: {$hint}", [
+                    'status' => $status,
+                    'url'    => $url,
+                    'body'   => $response->body(),
+                ]);
                 break;
             }