fix serializing signals

packages/signals/src/read_only_signal.rs

@@ -15,6 +15,26 @@ impl<T: 'static, S: Storage<SignalData<T>>> From<Signal<T, S>> for ReadOnlySigna
     }
 }
 
+#[cfg(feature = "serde")]
+impl<T: serde::Serialize + 'static, Store: Storage<SignalData<T>>> serde::Serialize
+    for ReadOnlySignal<T, Store>
+{
+    fn serialize<S: serde::Serializer>(&self, serializer: S) -> Result<S::Ok, S::Error> {
+        self.read().serialize(serializer)
+    }
+}
+
+#[cfg(feature = "serde")]
+impl<'de, T: serde::Deserialize<'de> + 'static, Store: Storage<SignalData<T>>>
+    serde::Deserialize<'de> for ReadOnlySignal<T, Store>
+{
+    fn deserialize<D: serde::Deserializer<'de>>(deserializer: D) -> Result<Self, D::Error> {
+        Ok(Self::new_maybe_sync(Signal::new_maybe_sync(
+            T::deserialize(deserializer)?,
+        )))
+    }
+}
+
 impl<T: 'static> ReadOnlySignal<T> {
     /// Create a new read-only signal.
     #[track_caller]