Add environment vairables when create new project

### What problem are you trying to solve?

Love the new UI but there is no way I can set environment vairables like db url when creating new project from github repo. this makes the first deployment failed and block the whole project creation process.

An alternative is create a blank project first then update env in settings then link the project again, but this make the UX worse.

Also, another problem is when copy/pasting the env variables, if you copy the whole .env file content like:

```
DB_URL=xxx
DB_USER=xxx
DB_PASS=xxx
```
then paste into this field in settings, all content will be in the first input normaly:

On vercel, it will try to parse it then create all three variables on UI and fill in the forms perfectly for you, this is very smooth on the UX. I think this improvement really worth being done.

### Describe the solution you'd like

give me some form fields to fill the required environment vairables.

### Describe alternatives you've considered

Or let me create the project even the first deployment is failed, then I can set the required environment vairables in project settings and trigger the deployment again.

The UX on Vercel about this project creation process is very good btw.

### Documentation, Adoption, Migration Strategy

_No response_