refactor(catalog): Complete catalog refactor to simplify its data model and its querying.

source commits: refactor/catalog

app/Domains/Catalog/Models/ItemAttribute.php

@@ -0,0 +1,38 @@
+<?php
+
+namespace App\Domains\Catalog\Models;
+
+use Illuminate\Database\Eloquent\Attributes\Fillable;
+use Illuminate\Database\Eloquent\Factories\HasFactory;
+use Illuminate\Database\Eloquent\Model;
+use Illuminate\Database\Eloquent\Relations\BelongsTo;
+use Illuminate\Database\Eloquent\Relations\HasMany;
+
+#[Fillable([
+    'catalog_item_id',
+    'attribute_id',
+])]
+class ItemAttribute extends Model
+{
+    use HasFactory;
+
+    protected $table = 'item_attributes';
+
+    /** @return BelongsTo<CatalogItem, $this> */
+    public function catalogItem(): BelongsTo
+    {
+        return $this->belongsTo(CatalogItem::class);
+    }
+
+    /** @return BelongsTo<Attribute, $this> */
+    public function attribute(): BelongsTo
+    {
+        return $this->belongsTo(Attribute::class);
+    }
+
+    /** @return HasMany<VariantDefinition, $this> */
+    public function variantDefinitions(): HasMany
+    {
+        return $this->hasMany(VariantDefinition::class);
+    }
+}