Fix devise not rendering errors as flash messages

https://github.com/heartcombo/devise/issues/5446

closes #63

app/controllers/turbo_controller.rb

@@ -0,0 +1,18 @@
+class TurboController < ApplicationController
+  class Responder < ActionController::Responder
+    def to_turbo_stream
+      controller.render(options.merge(formats: :html))
+    rescue ActionView::MissingTemplate => error
+      if get?
+        raise error
+      elsif has_errors? && default_action
+        render rendering_options.merge(formats: :html, status: :unprocessable_entity)
+      else
+        redirect_to navigation_location
+      end
+    end
+  end
+
+  self.responder = Responder
+  respond_to :html, :turbo_stream
+end