Add @see location for macros & mixins to PhpDoc

[riesjart]

Summary

This PR adds an @see with the macro/mixin definition location to PhpDoc.

Macro example

Logic:

class CollectionServiceProvider
{
    public function boot(): void
    {
        \Illuminate\Support\Collection::macro('toEloquent', function(): \Illuminate\Database\Eloquent\Collection {

            return \Illuminate\Database\Eloquent\Collection::make($this);
        });
    }
}

IDE helper:

/**
 * @see \Collection\CollectionServiceProvider::boot()
 * @return \Illuminate\Database\Eloquent\Collection
 * @static
 */
public static function toEloquent()
{
    return \Illuminate\Support\Collection::toEloquent();
}

Mixin example

Logic:

/**
 * @mixin \Illuminate\Support\Collection
 */
class CollectionMixin
{
    public function toEloquent(): Closure
    {
        return function(): \Illuminate\Database\Eloquent\Collection {

            return \Illuminate\Database\Eloquent\Collection::make($this);
        };
    }
}

IDE helper:

/**
 * @see \Collection\CollectionMixin::toEloquent()
 * @return \Illuminate\Database\Eloquent\Collection
 * @static
 */
public static function toEloquent()
{
    return \Illuminate\Support\Collection::toEloquent();
}

Type of change

• New feature (non-breaking change which adds functionality)

[mfn]

Nice one, LGTM!

We don't have any testing infrastructure for this, but tested it one a private project, found no issues

@barryvdh IMHO good to merge!