🩹(frontend) prevent support toggle when Crisp chat is blocked

Some users have ad-blockers or privacy extensions that prevent the Crisp chat
widget script from loading properly. This was causing the support toggle to
still display in rooms, but clicking it had no effect since Crisp was blocked.

This ensures users don't see an inactive support button when their browser
is blocking Crisp functionality.

src/frontend/src/features/support/hooks/useSupport.tsx

@@ -31,7 +31,17 @@ export const useSupport = ({ id }: useSupportProps) => {
   return null
 }
 
+// Some users may block Crisp chat widget with browser ad blockers or anti-tracking plugins
+// So we need to safely check if Crisp is available and not blocked
+const isCrispAvailable = () => {
+  try {
+    return !!window?.$crisp?.is
+  } catch {
+    return false
+  }
+}
+
 export const useIsSupportEnabled = () => {
   const { data } = useConfig()
-  return !!data?.support?.id
+  return !!data?.support?.id && isCrispAvailable()
 }