feat: add transactional approval workflow

app/Domain/Approvals/Models/ApprovalAction.php

@@ -0,0 +1,30 @@
+<?php
+
+namespace App\Domain\Approvals\Models;
+
+use App\Domain\Reservations\Models\Reservation;
+use App\Models\User;
+use Illuminate\Database\Eloquent\Model;
+use Illuminate\Database\Eloquent\Relations\BelongsTo;
+
+class ApprovalAction extends Model
+{
+    public const UPDATED_AT = null;
+
+    protected $fillable = [
+        'reservation_id', 'actor_id', 'action', 'previous_status', 'new_status',
+        'comment', 'created_at',
+    ];
+
+    /** @return BelongsTo<Reservation, $this> */
+    public function reservation(): BelongsTo
+    {
+        return $this->belongsTo(Reservation::class);
+    }
+
+    /** @return BelongsTo<User, $this> */
+    public function actor(): BelongsTo
+    {
+        return $this->belongsTo(User::class, 'actor_id');
+    }
+}