Fixed toasts not disappearing after settings reload (#18535)

refs
https://www.notion.so/ghost/AdminX-feedback-27fc7f549bbf4a53bfa2e7b6e5643963?p=d8bb2da9a6534494ad5baf840bbfd785&pm=s

- The error state remains visible after navigating away from settings
- this fix resets the toast on initial load to ensure it doesn't persist
if not needed
---

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### <samp>🤖 Generated by Copilot at 5c91fe7</samp>

Improved notifications on settings page using `toast` function. Cleared
old notifications on initial load to avoid confusion.

apps/admin-x-settings/src/MainContent.tsx

@@ -6,6 +6,7 @@ import Users from './components/settings/general/Users';
 import useRouting from './hooks/useRouting';
 import {ReactNode, useEffect} from 'react';
 import {canAccessSettings, isEditorUser} from './api/users';
+import {toast} from 'react-hot-toast';
 import {topLevelBackdropClasses} from './admin-x-ds/global/modal/Modal';
 import {useGlobalData} from './components/providers/GlobalDataProvider';
 
@@ -25,6 +26,11 @@ const MainContent: React.FC = () => {
     const {currentUser} = useGlobalData();
     const {route, updateRoute, loadingModal} = useRouting();
 
+    useEffect(() => {
+        // resets any toasts that may have been left open on initial load
+        toast.remove();
+    }, []);
+
     useEffect(() => {
         if (!canAccessSettings(currentUser) && route !== `staff/${currentUser.slug}`) {
             updateRoute(`staff/${currentUser.slug}`);