Add support for multiple addGroup

[Simone4e]

Hello,

I tried this pattern for stack multiple addGroup and try to group some category but doesnt work:

$r->addGroup('/admin', function (FastRoute\RouteCollector $r) {
       $r->addGroup('/company', function (FastRoute\RouteCollector $r) {

       }
});

[rbarden]

Not sure if you figured this out yet, but that should definitely work. For example:

$r->addGroup('/d', function ($r) {
    $r->addGroup('/c', function ($r) {
        $r->get('/b', fn() => 'valid');
    });
});

Generates GET /d/c/b as a valid route.

[Simone4e]

Not sure if you figured this out yet, but that should definitely work. For example:

$r->addGroup('/d', function ($r) {
    $r->addGroup('/c', function ($r) {
        $r->get('/b', fn() => 'valid');
    });
});

Generates GET /d/c/b as a valid route.

Idk why i tried and failed in the first time, but now works thanks