Add route to redirect to another instance

src/invidious.cr

@@ -314,6 +314,7 @@ Invidious::Routing.get "/shorts/:id", Invidious::Routes::Watch, :redirect
 Invidious::Routing.get "/w/:id", Invidious::Routes::Watch, :redirect
 Invidious::Routing.get "/v/:id", Invidious::Routes::Watch, :redirect
 Invidious::Routing.get "/e/:id", Invidious::Routes::Watch, :redirect
+Invidious::Routing.get "/redirect", Invidious::Routes::Misc, :cross_instance_redirect
 
 Invidious::Routing.get "/embed/", Invidious::Routes::Embed, :redirect
 Invidious::Routing.get "/embed/:id", Invidious::Routes::Embed, :show

src/invidious/routes/misc.cr

@@ -35,4 +35,10 @@ class Invidious::Routes::Misc < Invidious::Routes::BaseRoute
     locale = LOCALES[env.get("preferences").as(Preferences).locale]?
     rendered "licenses"
   end
+
+  def cross_instance_redirect(env)
+      id = env.params.query["id"]
+      instance_url = fetch_random_instance
+      env.redirect "https://#{instance_url}/watch?v=#{id}"
+  end
 end