Move remaining routes to new structure

src/invidious/routes/playlists.cr

@@ -443,4 +443,15 @@ module Invidious::Routes::Playlists
 
     templated "mix"
   end
+
+  # Undocumented, creates anonymous playlist with specified 'video_ids', max 50 videos
+  def self.watch_videos(env)
+    response = YT_POOL.client &.get(env.request.resource)
+    if url = response.headers["Location"]?
+      url = URI.parse(url).request_target
+      return env.redirect url
+    end
+
+    env.response.status_code = response.status_code
+  end
 end