[Doc] Mention that httpError triggers a notification

docs/Admin.md

@@ -906,7 +906,7 @@ React-admin uses [React Query](https://tanstack.com/query/v5/) to fetch, cache a
   * The query is optionally configured with a refetch interval
 * Query results that are no longer used in the current page are labeled as "inactive" and remain in the cache in case they are used again at a later time.
 * By default, "inactive" queries are garbage collected after 5 minutes.
-* Queries that fail are silently retried 3 times, with exponential backoff delay before capturing and displaying an error to the UI.
+* Queries that fail are silently retried 3 times, with exponential backoff delay before capturing and displaying an error notification to the UI.
 * Query results by default are structurally shared to detect if data have actually changed and if not, the data reference remains unchanged to better help with value stabilization in regard to `useMemo` and `useCallback`. 
 
 If you want to override the react-query default query and mutation default options, or use a specific client or mutation cache, you can create your own `QueryClient` instance and pass it to the `<Admin queryClient>` prop:

docs/DataProviderWriting.md

@@ -440,6 +440,8 @@ export default {
 };
 ```
 
+**Note**: Throwing an `httpError` in your `dataProvider` will result in a notify popup appearing in your admin UI.
+
 ## Handling Authentication
 
 Your API probably requires some form of authentication (e.g. a token in the `Authorization` header). It's the responsibility of [the `authProvider`](./Authentication.md) to log the user in and obtain the authentication data. React-admin doesn't provide any particular way of communicating this authentication data to the Data Provider. Most of the time, storing the authentication data in the  `localStorage` is the best choice - and allows uses to open multiple tabs without having to log in again.

docs/DataProviders.md

@@ -68,7 +68,7 @@ React-admin uses [React Query](https://tanstack.com/query/v5/) to fetch, cache,
   * The query is optionally configured with a refetch interval
 * Query results that are no longer used in the current page are labeled as "inactive" and remain in the cache in case they are used again later.
 * By default, "inactive" queries are garbage collected after 5 minutes.
-* Queries that fail are silently retried 3 times, with exponential backoff delay before capturing and displaying an error to the UI.
+* Queries that fail are silently retried 3 times, with exponential backoff delay before capturing and displaying an error notification to the UI.
 * Query results by default are structurally shared to detect if data has actually changed, and if not, the data reference remains unchanged to better help with value stabilization in regard to `useMemo` and `useCallback`.
 
 If you want to override the react-query default query and mutation options, or use a specific client or mutation cache, you can create your own `QueryClient` instance and pass it to the `<Admin queryClient>` prop: