Refactor: replace whitelist_mode mentions with limited_federation_mode (#26252)

.rubocop_todo.yml

app/controllers/accounts_controller.rb

app/controllers/admin/instances_controller.rb

app/controllers/api/base_controller.rb

app/controllers/api/v1/instances/activity_controller.rb

app/controllers/api/v1/instances/domain_blocks_controller.rb

...lers/api/v1/instances/extended_descriptions_controller.rb

app/controllers/api/v1/instances/peers_controller.rb

...ntrollers/api/v1/instances/privacy_policies_controller.rb

app/controllers/api/v1/instances/rules_controller.rb

...lers/api/v1/instances/translation_languages_controller.rb

app/controllers/api/v1/instances_controller.rb

app/controllers/api/v1/peers/search_controller.rb

app/controllers/application_controller.rb

app/controllers/concerns/account_owned_concern.rb

app/controllers/concerns/api_caching_concern.rb

app/controllers/follower_accounts_controller.rb

app/controllers/following_accounts_controller.rb

app/controllers/media_controller.rb

app/controllers/media_proxy_controller.rb