Feature request: Add --debug flag to installer

[kaidesu]

Is your feature request related to a problem? Please describe.

We used to have a --dev flag to enable debug mode in Laravel. We've removed this command in favor of having dedicated --homestead and --valet commands instead. However, it would still be nice to be able to explicitly set debug mode on installation for other purposes.

Describe the solution you'd like

Add a --debug flag to the installer to enable Laravel's debug mode (APP_DEBUG = true)

Feature request checklist

• This is a single feature (i.e. not a re-write of the entire CMS)
• The title starts with "Feature request: " and is followed by a clear feature name (Ex: Feature request: add konami code to control panel)
• I have searched for existing issues and to the best of my knowledge this is not a duplicate