Remove Salmon and PubSubHubbub (#11205)

* Remove Salmon and PubSubHubbub endpoints

* Add error when trying to follow OStatus accounts

* Fix new accounts not being created in ResolveAccountService

config/routes.rb

@@ -154,7 +154,6 @@ Rails.application.routes.draw do
   namespace :admin do
     get '/dashboard', to: 'dashboard#index'
 
-    resources :subscriptions, only: [:index]
     resources :domain_blocks, only: [:new, :create, :show, :destroy]
     resources :email_domain_blocks, only: [:index, :new, :create, :destroy]
     resources :action_logs, only: [:index]
@@ -191,8 +190,6 @@ Rails.application.routes.draw do
 
     resources :accounts, only: [:index, :show] do
       member do
-        post :subscribe
-        post :unsubscribe
         post :enable
         post :unsilence
         post :unsuspend
@@ -257,16 +254,6 @@ Rails.application.routes.draw do
   get '/admin', to: redirect('/admin/dashboard', status: 302)
 
   namespace :api do
-    # PubSubHubbub outgoing subscriptions
-    resources :subscriptions, only: [:show]
-    post '/subscriptions/:id', to: 'subscriptions#update'
-
-    # PubSubHubbub incoming subscriptions
-    post '/push', to: 'push#update', as: :push
-
-    # Salmon
-    post '/salmon/:id', to: 'salmon#update', as: :salmon
-
     # OEmbed
     get '/oembed', to: 'oembed#show', as: :oembed
 
@@ -318,7 +305,6 @@ Rails.application.routes.draw do
 
       get '/search', to: 'search#index', as: :search
 
-      resources :follows,      only: [:create]
       resources :media,        only: [:create, :update]
       resources :blocks,       only: [:index]
       resources :mutes,        only: [:index]