introduce rector to perform better laravel upgrades

[comes]

I suggest using rector for upgrades to support this project and modernize the code base.

This PR provides a rector dependency and a very basic configuration. It also does some minor upgrades to the code base that are part of the upgrade guidelines when upgrading to laravel 11.

To learn more about rector, see rector.org

To run rector, you need to run ./vendor/bin/rector.

This PR is one of many to improve the OpenLitterMap code base and modernize it for a brighter future regarding readability and scalability.

All the best @xlcrr

Jeremias

[xlcrr]

Thanks @comes its been on my todo list for a while, I'm happy with 90% of this but it breaks a little bit of my coding style for better readability and don't have the time to dig into new rules at the moment. I'm focused on a few other things at the moment, ill come back to this when I can

Thanks!