rephrased the runWithClient section in dart

docs/platforms/dart/integrations/http-integration.mdx

@@ -4,9 +4,9 @@ description: "Learn more about the Sentry HTTP integration for the Dart SDK."
 sidebar_order: 2
 ---
 
-## Using the `runWithClient` function
+## Using the `SentryHttpClient` function
 
-With [`runWithClient`](https://pub.dev/documentation/http/latest/http/runWithClient.html), you can define a global `SentryHttpClient` and run it in its own [`Zone`](https://api.dart.dev/stable/3.4.4/dart-async/Zone-class.html).
+Depending on your use case, you can either use the `SentryHttpClient` directly and call its methods (see the `default` tab), or you can use the [`runWithClient`](https://pub.dev/documentation/http/latest/http/runWithClient.html) function (see the `runWithClient` tab). With [`runWithClient`](https://pub.dev/documentation/http/latest/http/runWithClient.html), a fresh instance of the `client` is used and the other instances are not affected. It also runs in a separate [`Zone`](https://api.dart.dev/stable/3.5.0/dart-async/Zone-class.html), allowing you to override the functionality of the existing [`Zone`](https://api.dart.dev/stable/3.5.0/dart-async/Zone-class.html).
 
 ### Usage