fix: fix mut binding and unused import warnings in Kani proofs

crates/domain/src/proofs.rs

@@ -3,7 +3,7 @@ mod kani_proofs {
     use crate::capability::{Capability, CapabilityTable};
     use crate::resource::Resource;
     use crate::thread::{BlockReason, Thread, ThreadState};
-    use types::bounded::{CapSlot, Priority};
+    use types::bounded::Priority;
     use types::generation::Generation;
     use types::id::{CoreId, EndpointId, ProcessId, ThreadId};
     use types::permission::{Permission, PermissionSet};
@@ -137,7 +137,7 @@ mod kani_proofs {
         kani::assume(prio_val <= 31);
         let prio = Priority::new(prio_val).unwrap();
 
-        let thread = Thread::new(
+        let mut thread = Thread::new(
             ThreadId::from_raw(0),
             ProcessId::from_raw(0),
             prio,