refactor: improve type safety in abstract classes

- Add explicit return types to AbstractNativeInteger methods
- Add explicit return types to AbstractBigInteger methods
- Improve method signatures for better type safety
- Maintain backward compatibility while enhancing type checking

Author: nejc

src/Abstract/AbstractBigInteger.php

@@ -79,6 +79,7 @@ protected function setValue(int|string $value): void
     }
 
 
+
     /**
      * @param BigIntegerInterface|NativeIntegerInterface $other
      * @param callable $operation

src/Abstract/AbstractNativeInteger.php

@@ -4,6 +4,7 @@
 
 namespace Nejcc\PhpDatatypes\Abstract;
 
+use Nejcc\PhpDatatypes\Attributes\Range;
 use Nejcc\PhpDatatypes\Interfaces\NativeIntegerInterface;
 use Nejcc\PhpDatatypes\Traits\NativeArithmeticOperationsTrait;
 use Nejcc\PhpDatatypes\Traits\NativeIntegerComparisonTrait;
@@ -72,6 +73,7 @@ protected function setValue(int $value): void
         $this->value = $value;
     }
 
+
     /**
      * @param NativeIntegerInterface $other
      * @param callable $operation