fix(audit): remove unwrap from target shutdown path (#2668)

Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>

crates/audit/src/registry.rs

@@ -200,8 +200,8 @@ impl AuditRegistry {
             }
         }
 
-        if !errors.is_empty() {
+        if let Some(error) = errors.into_iter().next() {
-            return Err(AuditError::Target(errors.into_iter().next().unwrap()));
+            return Err(AuditError::Target(error));
         }
 
         Ok(())