fix: require that resources, abilities, and caveats are Send + Sync

Co-authored-by: Philipp Krüger <[email protected]>

src/semantics/ability.rs

@@ -8,7 +8,7 @@ use dyn_clone::{clone_trait_object, DynClone};
 use super::caveat::Caveat;
 
 /// An ability defined as part of a semantics
-pub trait Ability: Display + DynClone + Downcast + 'static {
+pub trait Ability: Send + Sync + Display + DynClone + Downcast + 'static {
     /// Returns true if self is a valid attenuation of other
     fn is_valid_attenuation(&self, other: &dyn Ability) -> bool;
 

src/semantics/caveat.rs

@@ -8,7 +8,7 @@ use erased_serde::serialize_trait_object;
 use serde::{Deserialize, Serialize};
 
 /// A caveat defined as part of a semantics
-pub trait Caveat: DynClone + Downcast + erased_serde::Serialize + 'static {
+pub trait Caveat: Send + Sync + DynClone + Downcast + erased_serde::Serialize + 'static {
     /// Returns true if the caveat is valid
     fn is_valid(&self) -> bool;
 

src/semantics/resource.rs

@@ -6,7 +6,7 @@ use downcast_rs::{impl_downcast, Downcast};
 use dyn_clone::{clone_trait_object, DynClone};
 
 /// A resource defined as part of a semantics
-pub trait Resource: Display + DynClone + Downcast + 'static {
+pub trait Resource: Send + Sync + Display + DynClone + Downcast + 'static {
     /// Returns true if self is a valid attenuation of other
     fn is_valid_attenuation(&self, other: &dyn Resource) -> bool;
 }