Fix insert() TypeError when primary key is typed as int

[enlivenapp]

I created a subclass with public int $id and inserted a new record:

class User extends \flight\ActiveRecord {
    public function __construct($pdo = null) {
        parent::__construct($pdo, 'users');
    }
    public int $id;
    public string $name;
}

$user = new User($pdo);
$user->name = 'John';
$user->insert();

I expected the insert to succeed and $user->id to be set to the new auto-increment value.

Instead, it throws TypeError: Cannot assign string to property User::$id of type int, because lastInsertId() returns a string.

Subclasses without a typed primary key are not affected.

Tests included. All existing tests continue to pass.

[enlivenapp]

Closed, too much separation. see #33 . Sorry for the noise.