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.

從 `ng new` 命令的進入點開始，追蹤它如何處理現有的專案資料夾。加入所要求的確認或錯誤行為，包括替代名稱的指引，並驗證現有檔案不會被取代。

由索引模型根據 Issue 內容生成。