fix : 모델, BOM 구성 수정

- 설계용 모델, BOM 기능 추가

app/Models/Design/BomTemplateItem.php

@@ -0,0 +1,23 @@
+<?php
+
+namespace App\Models\Design;
+
+use Illuminate\Database\Eloquent\Model;
+
+class BomTemplateItem extends Model
+{
+    protected $table = 'bom_template_items';
+
+    protected $fillable = [
+        'tenant_id','bom_template_id','ref_type','ref_id','qty','waste_rate','uom_id','notes','sort_order',
+    ];
+
+    protected $casts = [
+        'qty' => 'decimal:6',
+        'waste_rate' => 'decimal:6',
+    ];
+
+    public function template() {
+        return $this->belongsTo(BomTemplate::class, 'bom_template_id');
+    }
+}