fix: better reporting in class declaration

fix: better reporting unfinished property declaration

minor: `Class_$parent_class_name` and `$child_class_names`

fix: Uncaught TypeError: Osm\Runtime\Compilation\Properties\Merged::g…

…et_nullable(): Return value must be of type bool, null returned

fix: Uncaught TypeError: Osm\Runtime\Compilation\Properties\Merged::g…

…et_nullable(): Return value must be of type bool, null returned

fix: PHP 8.1 compatibility

fix: PHP 8.1 compatibility

minor: new `#[Serialized(not_having: 'children')]` attribute setting

fix: don't alias static trait method overridden by another static trait

minor: method reflection data