Admin protetto, dashboard KPI e aggiornamenti sito marketing.

Login admin con cambio password, metriche server (CPU/RAM/disco/banda), grafici e statistiche streaming; sezione piani ridimensionata.

Co-authored-by: Cursor <cursoragent@cursor.com>

backend/config/routes.rb

@@ -54,7 +54,13 @@ Rails.application.routes.draw do
   post "internal/validate_publish", to: "webhooks/mediamtx#validate_publish"
 
   namespace :admin do
+    get "login", to: "auth#new", as: :login
+    post "login", to: "auth#create"
+    delete "logout", to: "auth#destroy", as: :logout
+    resource :password, only: %i[edit update], controller: "passwords"
+
     root to: "dashboard#index"
+    get "metrics", to: "dashboard#metrics"
     resources :teams, only: %i[index show]
     resources :sessions, only: %i[index show]
   end