add bookmark back

app/Models/Bookmark.php

@@ -0,0 +1,10 @@
+<?php
+
+namespace App\Models;
+
+use Illuminate\Database\Eloquent\Model;
+
+class Bookmark extends Model
+{
+    protected $guarded = [];
+}

app/Models/User.php

@@ -2,6 +2,7 @@
 
 namespace App;
 
+use App\Models\Bookmark;
 use App\Models\Image;
 use App\Models\Memo;
 use App\Models\ToDoList;
@@ -64,6 +65,11 @@ class User extends Authenticatable
         return $this->hasMany(ToDoList::class);
     }
 
+    public function bookmarks() : HasMany
+    {
+        return $this->hasMany(Bookmark::class);
+    }
+
     public function images(): MorphMany
     {
         return $this->morphMany(Image::class, 'imageable');