[2.x] Drop Laravel 8.x support (and PHP < 8)

[timacdonald]

Dropping Laravel 8.x support as:

• Jetstream is only meant to be installed on "new applications". I interpret this as meaning composer create-project laravel/laravel app.

Adding conflict as:

• Vite is only supported in laravel/framework:^9.19.0.

Dropping support for PHP < 8.0.2 as:

• The current version of Laravel 9.x only supports PHP:^8.0.2.

I'm also not sure how Laravel approaches dropping version support with SemVer - especially when it comes to these started kits. I'm pretty sure dropping version support is not a "breaking change" in SemVer world.

Alternatively, we could back port Vite but this would probably also include ongoing feature improvements in laravel/framework around Vite as well.

Testing script:

composer create-project laravel/laravel jetstream-test \
  && cd jetstream-test \
  && composer require laravel/jetstream:drop-8.x-support-dev \
  && php artisan jetstream:install inertia \
  && sed -i "s/SESSION_DRIVER=database/SESSION_DRIVER=file/" .env \
  && npm install && npm run dev

php artisan serve

See also: laravel/breeze#167

[driesvints]

Thanks @timacdonald. You can also remove the old testbench version next time (I updated the composer.json just now).

[timacdonald]

thanks @driesvints - I didn't even consider that one! Will keep that in mind next time 👍