[FEATURE REQUEST] Add support for emulating request method with forms

Ruby on Rails on its own previously emulated request method by considering `_method` post parameter as an intended request method. Some things could happen here too even if the parameter is more obscure (security through obscurity 😅 ). There are some corner cases where you can't / won't want to alter the request via AJAX.

I think this could be a configurable feature for the router since it has side effects.

Start by reading the router's request handling and configuration entry points, then inspect any existing routing tests. Determine how Rails-style `_method` form parameters should select the intended method and how the behavior can be enabled or disabled safely. Done means the configurable behavior works for the supported methods and its side effects are covered by tests.

Written by the indexing model from the issue text.