Permette titolo, testo e link diversi per Android e iOS negli avvisi.

Separa i canali app e mostra il nodo ingest nelle sessioni admin.

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

backend/db/migrate/20260820180000_split_announcement_app_platforms.rb

@@ -0,0 +1,26 @@
+class SplitAnnouncementAppPlatforms < ActiveRecord::Migration[7.2]
+  def change
+    add_column :app_announcements, :show_on_android, :boolean, null: false, default: true
+    add_column :app_announcements, :show_on_ios, :boolean, null: false, default: true
+    add_column :app_announcements, :android_title, :string
+    add_column :app_announcements, :android_body, :text
+    add_column :app_announcements, :android_action_url, :string
+    add_column :app_announcements, :android_action_label, :string
+    add_column :app_announcements, :ios_title, :string
+    add_column :app_announcements, :ios_body, :text
+    add_column :app_announcements, :ios_action_url, :string
+    add_column :app_announcements, :ios_action_label, :string
+
+    reversible do |dir|
+      dir.up do
+        execute <<~SQL.squish
+          UPDATE app_announcements
+          SET show_on_android = show_on_app,
+              show_on_ios = show_on_app
+        SQL
+      end
+    end
+
+    remove_column :app_announcements, :show_on_app, :boolean, null: false, default: true
+  end
+end