Major update - added strict types, added code quality tools

[indy2kro]

Major update, modernize tool, contains breaking changes from previous version.

• Dropped support for php versions older than PHP 8.2 (not compatible with all changes)
• Added Rector support
• Added PHPinsights support
• Added PHPstan support
• Updated PHPstan to level 9
• Added strict_types to all files
• Updated github actions to use caching, added more tools execution

[bluemoehre]

Hey @indy2kro , many thanks for your contribution.

Would you be able to provide a merge request per topic? Mixing multiple improvements in a single PR slows down the process of reviewing and merging, and makes it difficult to discuss single things.

Small PRs significantly help in getting your code merged quickly and efficiently.

[indy2kro]

Hello,
Normally I would totally agree with your request and it sounds perfectly reasonable - the problem is that all the code quality tools interact with another (e.g. having a rector config might cause conflicts with another phpinsights configuration) - this is why they are all together.
The only item which could be in a separate PR could be related to git hooks - which indeed could be separated and done later (although that is usually the whole point - having them running automatically).