uri_for and uri_for_route not respecting prefix?

See #1743

Given this:

prefix undef;
get '/edit' => sub { say request->uri_for('/search') }; # '/search'
prefix '/info';
get '/update' => sub { say request->uri_for('/delete') }; # /delete - should be '/info/delete'

If 'forwardis called, we generate an error:uri_for_route called on a request instance without it`

For this test case:

get '/foo' => sub { print Dumper request; 1 }
get '/bar' => sub { print Dumper request; forward '/foo' };

HTTP request for /bar prior to forward:

[...]
uri_for_route => sub {
      package Dancer2::Core::App;
      use warnings;
      use strict;
      shift();
      $weak_self->uri_for_route(@_);
  },

http request for /bar after forward to /foo:

uri_for_route => undef

This behaviour is alluded to in the docs "when forward is executed, the current dispatch of the route is aborted, the request is modified". Can this be changed so that uri_for_route is preserved?

Start by tracing the request methods uri_for and uri_for_route, along with the forward and prefix entry points described in the examples. Reproduce the /info/delete case and the loss of uri_for_route after forwarding from /bar to /foo; done means the prefix is respected and uri_for_route remains available after forward.