Stage 12 — Online Store: public catalog + cart + orders

Schema:
- online_orders (token-tracked, status workflow, delivery method/fee)
- online_order_items (price snapshot, fulfilled flag)
- part_cross_refs (OEM/equivalent codes for search)
- parts.is_published (shop visibility)

Storefront (ShopController, tenant subdomain, /shop):
- Catalog with search across name/article/brand/cross-refs, category +
  in-stock filters, live stock, white-label themed layout
- Part detail page with cross-ref codes
- VIN search → VinDecoder → guided catalog search
- Session cart (per-tenant key), guest checkout, order confirmation page
- Respects settings.shop.enabled (404 when off); tenant-guarded

Part::searchPublished matches cross-ref articles via whereHas.

Order notifications (ShopOrderNotifier, best-effort):
- Staff: Web Push to active users
- Customer: Telegram if phone matches a linked client

Filament (tenant):
- OnlineOrderResource under "Magazin" nav group, status workflow,
  items relation, "Onorează" action issues stock via WarehouseService (FIFO)
- PartResource: is_published toggle + column + bulk publish/unpublish +
  CrossRefsRelationManager
- Settings: shop section (enable, delivery methods, fee, free-over)
- Landing page: shop button when enabled

Tests (6 new):
- catalog 404 when disabled; lists published only; cross-ref search;
  order placement (token + items + total); fulfill issues stock;
  cross-tenant token isolation

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

app/Models/Tenant/OnlineOrderItem.php

@@ -0,0 +1,43 @@
+<?php
+
+namespace App\Models\Tenant;
+
+use App\Models\Concerns\BelongsToTenant;
+use Illuminate\Database\Eloquent\Model;
+use Illuminate\Database\Eloquent\Relations\BelongsTo;
+
+class OnlineOrderItem extends Model
+{
+    use BelongsToTenant;
+
+    protected $fillable = [
+        'company_id', 'online_order_id', 'part_id',
+        'name', 'article', 'qty', 'price', 'total', 'fulfilled',
+    ];
+
+    protected $casts = [
+        'qty' => 'decimal:2',
+        'price' => 'decimal:2',
+        'total' => 'decimal:2',
+        'fulfilled' => 'boolean',
+    ];
+
+    public function order(): BelongsTo
+    {
+        return $this->belongsTo(OnlineOrder::class, 'online_order_id');
+    }
+
+    public function part(): BelongsTo
+    {
+        return $this->belongsTo(Part::class);
+    }
+
+    protected static function booted(): void
+    {
+        static::saving(function (self $row) {
+            $row->total = round((float) $row->qty * (float) $row->price, 2);
+        });
+        static::saved(fn (self $row) => $row->order?->recalcTotal());
+        static::deleted(fn (self $row) => $row->order?->recalcTotal());
+    }
+}