add error message when overlapping fullstack features are enabled

packages/fullstack/src/lib.rs

@@ -64,3 +64,10 @@ pub mod prelude {
 
     pub use hooks::{server_cached::server_cached, server_future::use_server_future};
 }
+
+// Warn users about overlapping features
+#[cfg(all(feature = "ssr", feature = "web"))]
+compile_error!("The `ssr` feature (enabled by `warp`, `axum`, or `salvo`) and `web` feature are overlapping. Please choose one or the other.");
+
+#[cfg(all(feature = "ssr", feature = "desktop"))]
+compile_error!("The `ssr` feature (enabled by `warp`, `axum`, or `salvo`) and `desktop` feature are overlapping. Please choose one or the other.");