Ask for recreating ( overwritting files) the current project folder

### Command

new

### Description

I'm new to Angular and I just started using its CLI, it's easy to use and I appreciate it a lot.

However, I have noticed that it misses ( based on my experience with NextJS CLI) to ask the developer if the project ( folder ) exists and if he is sure that he wants to recreate the project and remove the old files.

##### STEP 01

`ng new my app`

##### STEP 02

Write some code and save the changes.

##### STEP 03

`ng new my app`

### Expected

The CLI asks that the project name exists.

### Current

Create a new project with the same name and replace older files with the new ones.

### Describe the solution you'd like

The CLI should inform the developer that the project name exists and recommends alternative names.

### Describe alternatives you've considered

Invoke an error and enforce the user to change the name of the project name.

`ng new` コマンドのエントリーポイントから開始し、既存のプロジェクトフォルダーをどのように処理するかを追跡します。代替名の案内を含む、要求された確認またはエラーの動作を追加し、既存のファイルが置き換えられないことを確認します。

索引モデルが issue の本文から書いたものです。