refactor: move backend in apps/backend

apps/backend/app/Models/Event.php

@@ -0,0 +1,22 @@
+<?php
+
+namespace apps\backend\app\Models;
+
+use Illuminate\Database\Eloquent\Factories\HasFactory;
+use Illuminate\Database\Eloquent\Model;
+
+class Event extends Model
+{
+    use HasFactory;
+    protected $fillable = [
+        "name",
+        "description",
+        "event_photo_path",
+        'start',
+        'end',
+    ];
+
+    public function tasks() {
+        return $this->hasMany(Task::class, 'events_id');
+    }
+}