add with_client option

Author: EItanya

crates/rmcp/src/transport/sse.rs

@@ -108,6 +108,17 @@ impl ReqwestSseClient {
             sse_url: url,
         })
     }
+
+    pub async fn new_with_client<U>(url: U, client: HttpClient) -> Result<Self, SseTransportError>
+    where
+        U: IntoUrl,
+    {
+        let url = url.into_url()?;
+        Ok(Self {
+            http_client: client,
+            sse_url: url,
+        })
+    }
 }
 
 impl SseClient for ReqwestSseClient {