Add remote interaction dialog for toots (#8202)

* Add remote interaction dialog for toots

* Change AuthorizeFollow into AuthorizeInteraction, support statuses

* Update brakeman.ignore

* Adjust how interaction buttons are display on public pages

* Fix tests

app/controllers/remote_interaction_controller.rb

@@ -0,0 +1,48 @@
+# frozen_string_literal: true
+
+class RemoteInteractionController < ApplicationController
+  include Authorization
+
+  layout 'modal'
+
+  before_action :set_status
+  before_action :set_body_classes
+
+  def new
+    @remote_follow = RemoteFollow.new(session_params)
+  end
+
+  def create
+    @remote_follow = RemoteFollow.new(resource_params)
+
+    if @remote_follow.valid?
+      session[:remote_follow] = @remote_follow.acct
+      redirect_to @remote_follow.interact_address_for(@status)
+    else
+      render :new
+    end
+  end
+
+  private
+
+  def resource_params
+    params.require(:remote_follow).permit(:acct)
+  end
+
+  def session_params
+    { acct: session[:remote_follow] }
+  end
+
+  def set_status
+    @status = Status.find(params[:id])
+    authorize @status, :show?
+  rescue Mastodon::NotPermittedError
+    # Reraise in order to get a 404
+    raise ActiveRecord::RecordNotFound
+  end
+
+  def set_body_classes
+    @body_classes = 'modal-layout'
+    @hide_header  = true
+  end
+end