Change dismissed banners to be stored server-side

Fixes #25957

app/javascript/mastodon/components/dismissable_banner.tsx

@@ -1,3 +1,8 @@
+/* eslint-disable @typescript-eslint/no-unsafe-call,
+                  @typescript-eslint/no-unsafe-return,
+                  @typescript-eslint/no-unsafe-assignment,
+                  @typescript-eslint/no-unsafe-member-access
+                  -- the settings store is not yet typed */
 import type { PropsWithChildren } from 'react';
 import { useCallback, useState } from 'react';
 
@@ -5,7 +10,9 @@ import { defineMessages, useIntl } from 'react-intl';
 
 import { ReactComponent as CloseIcon } from '@material-symbols/svg-600/outlined/close.svg';
 
+import { changeSetting } from 'mastodon/actions/settings';
 import { bannerSettings } from 'mastodon/settings';
+import { useAppSelector, useAppDispatch } from 'mastodon/store';
 
 import { IconButton } from './icon_button';
 
@@ -21,13 +28,23 @@ export const DismissableBanner: React.FC<PropsWithChildren<Props>> = ({
   id,
   children,
 }) => {
-  const [visible, setVisible] = useState(!bannerSettings.get(id));
+  const dismissed = useAppSelector((state) =>
+    state.settings.getIn(['dismissed_banners', id]),
+  );
+  const dispatch = useAppDispatch();
+
+  const [visible, setVisible] = useState(!bannerSettings.get(id) && !dismissed);
   const intl = useIntl();
 
   const handleDismiss = useCallback(() => {
     setVisible(false);
     bannerSettings.set(id, true);
-  }, [id]);
+    dispatch(changeSetting(['dismissed_banners', id], true));
+  }, [id, dispatch]);
+
+  if (!visible && !dismissed) {
+    dispatch(changeSetting(['dismissed_banners', id], true));
+  }
 
   if (!visible) {
     return null;

app/javascript/mastodon/reducers/settings.js

@@ -100,6 +100,15 @@ const initialState = ImmutableMap({
       body: '',
     }),
   }),
+
+  dismissed_banners: ImmutableMap({
+    'public_timeline': false,
+    'community_timeline': false,
+    'home.explore_prompt': false,
+    'explore/links': false,
+    'explore/statuses': false,
+    'explore/tags': false,
+  }),
 });
 
 const defaultColumns = fromJS([