Update repo configs from https://getscaffold.dev/

[AlexSkrypnyk]

Download the latest code from Scaffold repo (actual code, not the release).

• Update package.json with the structure from Scaffold. Preserve the values of the existing fields, but order the fields as per Scaffold's package.json. Add missing fields.
• Add Renovate config from Scaffold
• Add/update all GitHub actions and configs to be per Scaffold.
• Update readme to use the structure from Scaffold, including the generated logo (circle). Transfer the usage examples into the readme structure from Scaffold
• Add PHPStan config and fix all newly found violations
• Reformat package.json to have indents and sorting as per the Scaffold.

Make sure that CI passes.

Similar task for reference: AlexSkrypnyk/shellvar#17