I want to create a custom package for laravel 5.3 but I get the error

It's my first time doing this.   
My package map

   vendor/
  kenny/
    proxmox/
      src/
        ProxmoxServiceProvider.php
      composer.json

my package composer

{
    "name": "Kenny/Proxmox",
    "description": "NULL",
    "type": "Package Type (e.g. library, project, metapackage, composer-plugin) []: NULL",
    "require": {
        
    },
    "authors": [
        {
            "name": "Kenny Sinkeler",
            "email": "info@kennysinkeler.nl"
        }
    ], 
    
        "psr-4": {
           
            "Kenny\\Proxmox\\": "/src"
        }
    },


}

my ProxmoxServiceProvider.php

<?php
namespace Kenny\Proxmox;

use Illuminate\Support\ServiceProvider;

class ProxmoxServiceProvider extends ServiceProvider
{
    /**
     * Bootstrap the application services.
     *
     * @return void
     */
    public function boot()
    {
        //
    }

    /**
     * Register the application services.
     *
     * @return void
     */
    public function register()
    {
        //
    }
}

and of course my main composer.json

{
    "name": "laravel/laravel",
    "description": "The Laravel Framework.",
    "keywords": ["framework", "laravel"],
    "license": "MIT",
    "type": "project",
    "require": {
        "php": ">=5.6.4",
        "laravel/framework": "5.3.*"
       
    },
    "require-dev": {
        "fzaninotto/faker": "~1.4",
        "mockery/mockery": "0.9.*",
        "phpunit/phpunit": "~5.0",
        "symfony/css-selector": "3.1.*",
        "symfony/dom-crawler": "3.1.*"

    },
    "autoload": {
        "classmap": [
            "database"
        ],
        "psr-4": {
            "App\\": "app/",
            "Kenny\\Proxmox\\" :"vendor/kenny/Proxmox/src"
        }
    },
    "autoload-dev": {
        "classmap": [
            "tests/TestCase.php",
            "app/User.php"
        ]
    },
    "scripts": {
        "post-root-package-install": [
            "php -r \"file_exists('.env') || copy('.env.example', '.env');\""
        ],
        "post-create-project-cmd": [
            "php artisan key:generate"
        ],
        "post-install-cmd": [
            "Illuminate\\Foundation\\ComposerScripts::postInstall",
            "php artisan optimize"
        ],
        "post-update-cmd": [
            "Illuminate\\Foundation\\ComposerScripts::postUpdate",
            "php artisan optimize"
        ]
    },
    "config": {
        "preferred-install": "dist"
    }
}

I don't know what is wrong. I have used auto-dump but that was not working.
Maybe I have a wrong code. Idk please help me!