fix: flag schema derive on schemars feature (#966)

crates/rmcp/src/lib.rs

@@ -34,7 +34,7 @@ pub mod transport;
 pub use pastey::paste;
 #[cfg(all(feature = "macros", feature = "server"))]
 pub use rmcp_macros::*;
-#[cfg(any(feature = "server", feature = "schemars"))]
+#[cfg(feature = "schemars")]
 pub use schemars;
 #[cfg(feature = "macros")]
 pub use serde;

crates/rmcp/src/model.rs

@@ -66,7 +66,7 @@ macro_rules! object {
 /// without returning any specific data.
 #[derive(Debug, Serialize, Deserialize, Clone, PartialEq, Copy, Eq)]
 #[serde(deny_unknown_fields)]
-#[cfg_attr(feature = "server", derive(schemars::JsonSchema))]
+#[cfg_attr(feature = "schemars", derive(schemars::JsonSchema))]
 #[expect(clippy::exhaustive_structs, reason = "intentionally exhaustive")]
 pub struct EmptyObject {}