Added Item model, resource and its API.

Updated Category model to have Items.

app/Models/Item.php

@@ -0,0 +1,26 @@
+<?php
+
+namespace App\Models;
+
+use Illuminate\Database\Eloquent\Factories\HasFactory;
+use Illuminate\Database\Eloquent\Model;
+use Illuminate\Database\Eloquent\Relations\BelongsTo;
+
+class Item extends Model
+{
+    use HasFactory;
+
+    protected $fillable = [
+        'uuid',
+        'name',
+        'url',
+        'description',
+        'price',
+        'image',
+    ];
+
+    public function category(): BelongsTo
+    {
+        return $this->belongsTo(Category::class);
+    }
+}