Add reminder when about to post without alt text in web UI (#33760)

app/javascript/mastodon/features/ui/components/modal_root.jsx

@@ -37,6 +37,7 @@ import {
   ConfirmClearNotificationsModal,
   ConfirmLogOutModal,
   ConfirmFollowToListModal,
+  ConfirmMissingAltTextModal,
 } from './confirmation_modals';
 import ImageModal from './image_modal';
 import MediaModal from './media_modal';
@@ -58,6 +59,7 @@ export const MODAL_COMPONENTS = {
   'CONFIRM_CLEAR_NOTIFICATIONS': () => Promise.resolve({ default: ConfirmClearNotificationsModal }),
   'CONFIRM_LOG_OUT': () => Promise.resolve({ default: ConfirmLogOutModal }),
   'CONFIRM_FOLLOW_TO_LIST': () => Promise.resolve({ default: ConfirmFollowToListModal }),
+  'CONFIRM_MISSING_ALT_TEXT': () => Promise.resolve({ default: ConfirmMissingAltTextModal }),
   'MUTE': MuteModal,
   'BLOCK': BlockModal,
   'DOMAIN_BLOCK': DomainBlockModal,