update

app/Models/UserAchievement.php

@@ -0,0 +1,42 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Models;
+
+use Illuminate\Database\Eloquent\Factories\HasFactory;
+use Illuminate\Database\Eloquent\Model;
+use Illuminate\Database\Eloquent\Relations\BelongsTo;
+use App\Models\Achievement;
+
+class UserAchievement extends Model
+{
+    use HasFactory;
+
+    public $timestamps = false;
+
+    protected $fillable = [
+        'user_id',
+        'achievement_id',
+        'unlocked_at',
+    ];
+
+    protected function casts(): array
+    {
+        return [
+            'user_id' => 'integer',
+            'achievement_id' => 'integer',
+            'unlocked_at' => 'datetime',
+        ];
+    }
+
+    public function user(): BelongsTo
+    {
+        return $this->belongsTo(User::class);
+    }
+
+    public function achievement(): BelongsTo
+    {
+        return $this->belongsTo(Achievement::class, 'achievement_id');
+    }
+}