Add Shopify inventory sync and order webhook

- Migration: shopify_variant_id on products_sizes, shopify_order_id on products_sales
- ShopifyService: paginated REST client (2024-10 API)
- shopify:map — one-time command to link variants by SKU
- shopify:sync — reconciliation command (Shopify is master)
- VerifyShopifyWebhook middleware: HMAC-SHA256 verification
- ShopifyWebhookController: idempotent orders/paid handler, FIFO inventory deduction
- Webhook route: POST /api/webhooks/shopify/orders-paid

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

app/Console/Commands/ShopifyMap.php

@@ -0,0 +1,57 @@
+<?php
+
+namespace App\Console\Commands;
+
+use App\Models\ProductSize;
+use App\Services\ShopifyService;
+use Illuminate\Console\Command;
+
+class ShopifyMap extends Command
+{
+    protected $signature   = 'shopify:map {--dry-run : Änderungen nur anzeigen, nichts speichern}';
+    protected $description = 'Verknüpft Shopify-Variant-IDs mit lokalen ProductSizes per SKU';
+
+    public function handle(ShopifyService $shopify): int
+    {
+        $dryRun = $this->option('dry-run');
+        $variants = $shopify->getAllVariants();
+
+        $this->info('Shopify-Varianten geladen: ' . count($variants));
+
+        $mapped = 0;
+        $skipped = 0;
+        $noSku = 0;
+
+        foreach ($variants as $variant) {
+            if (empty($variant['sku'])) {
+                $noSku++;
+                continue;
+            }
+
+            $size = ProductSize::where('sku', $variant['sku'])->first();
+
+            if (!$size) {
+                $this->warn("  SKU nicht gefunden: {$variant['sku']} ({$variant['product_title']})");
+                $skipped++;
+                continue;
+            }
+
+            if ($size->shopify_variant_id === $variant['id']) {
+                continue; // already correct
+            }
+
+            if (!$dryRun) {
+                $size->update(['shopify_variant_id' => $variant['id']]);
+            }
+
+            $this->line("  {$variant['sku']} → Variant-ID {$variant['id']}");
+            $mapped++;
+        }
+
+        $this->info("✓ {$mapped} verknüpft" . ($dryRun ? ' (dry-run)' : ''));
+        if ($skipped) $this->warn("⚠ {$skipped} SKUs lokal nicht gefunden");
+        if ($noSku)   $this->warn("⚠ {$noSku} Shopify-Varianten ohne SKU übersprungen");
+
+        return self::SUCCESS;
+    }
+}

app/Console/Commands/ShopifySync.php

@@ -0,0 +1,78 @@
+<?php
+
+namespace App\Console\Commands;
+
+use App\Models\ProductInventory;
+use App\Models\ProductSize;
+use App\Services\ShopifyService;
+use Illuminate\Console\Command;
+use Illuminate\Support\Facades\DB;
+
+class ShopifySync extends Command
+{
+    protected $signature   = 'shopify:sync {--dry-run : Änderungen nur anzeigen, nichts speichern}';
+    protected $description = 'Gleicht lokalen Lagerbestand mit Shopify-Inventar ab';
+
+    public function handle(ShopifyService $shopify): int
+    {
+        $dryRun = $this->option('dry-run');
+        $variants = $shopify->getAllVariants();
+
+        $added   = 0;
+        $removed = 0;
+        $inSync  = 0;
+
+        DB::transaction(function () use ($variants, $dryRun, &$added, &$removed, &$inSync) {
+            foreach ($variants as $variant) {
+                $size = ProductSize::where('shopify_variant_id', $variant['id'])->first();
+
+                if (!$size) {
+                    continue; // not mapped yet — run shopify:map first
+                }
+
+                $shopifyQty = $variant['inventory_quantity'];
+                $localQty   = ProductInventory::where('size_id', $size->id)
+                    ->whereNull('out_at')
+                    ->count();
+
+                if ($localQty === $shopifyQty) {
+                    $inSync++;
+                    continue;
+                }
+
+                $diff = $shopifyQty - $localQty;
+
+                if ($diff > 0) {
+                    // Shopify hat mehr → Einträge hinzufügen
+                    $this->line("  +{$diff} {$variant['product_title']} (SKU {$variant['sku']})");
+                    if (!$dryRun) {
+                        for ($i = 0; $i < $diff; $i++) {
+                            ProductInventory::create([
+                                'product_id' => $size->product_id,
+                                'size_id'    => $size->id,
+                            ]);
+                        }
+                    }
+                    $added += $diff;
+                } else {
+                    // Shopify hat weniger → älteste Einträge als ausgebucht markieren
+                    $excess = abs($diff);
+                    $this->line("  -{$excess} {$variant['product_title']} (SKU {$variant['sku']})");
+                    if (!$dryRun) {
+                        ProductInventory::where('size_id', $size->id)
+                            ->whereNull('out_at')
+                            ->oldest()
+                            ->limit($excess)
+                            ->update(['out_at' => now()]);
+                    }
+                    $removed += $excess;
+                }
+            }
+        });
+
+        $this->info("✓ Sync abgeschlossen" . ($dryRun ? ' (dry-run)' : ''));
+        $this->info("  In Sync: {$inSync} | Hinzugefügt: {$added} | Ausgebucht: {$removed}");
+
+        return self::SUCCESS;
+    }
+}