Improve decoding path segments

[kelunik]

See #15 (comment)

Here is my case:

• Path is /.well-known/mercure/subscriptions/https%3A%2F%2Fexample.com%2Fmy-other-topic
• The current code is transforming it to /.well-known/mercure/subscriptions/https://example.com/my-other-topic

It prevents fastroute to route correctly with the route /.well-known/mercure/subscriptions/{topic}. Maybe adding a test case with my case would be nice?

See also: https://github.com/amphp/http-server-router?tab=readme-ov-file#limitations

[kelunik]

Symfony seems to have the exact same behavior as we currently have: https://symfony.com/doc/current/routing.html#slash-characters-in-route-parameters