Take the layer-chain test's closure down to &dyn Operation

`clippy::borrowed_box` is denied by the workspace lint set, and the closure
added with the optics exclusion took `&Box<dyn Operation>` — a borrow of the
box rather than of the thing in it, which says nothing the plain trait object
does not.

Caught by `cargo clippy --workspace --all-targets -- -D warnings`, which is
what CI runs and what the workspace tests do not: a lint on test code only
appears when the tests are compiled as a clippy target.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

core/dr-pipeline/src/mask.rs

@@ -1500,7 +1500,7 @@ mod tests {
         let ids: Vec<&str> = layer.capabilities().iter().map(|c| c.id.0).collect();
 
         let global = crate::ops::chain();
-        let local_means_something = |op: &Box<dyn Operation>| {
+        let local_means_something = |op: &dyn Operation| {
             op.detail().is_none()
                 && !op
                     .descriptor()
@@ -1512,14 +1512,15 @@ mod tests {
             let id = op.descriptor().id.0;
             assert_eq!(
                 ids.contains(&id),
-                local_means_something(op),
+                local_means_something(op.as_ref()),
                 "{id} is offered as a local adjustment but cannot meaningfully \
                  be one, or is an ordinary point operation and has gone \
                  missing from a layer"
             );
         }
         assert!(
-            ids.len() < global.len() || global.iter().all(local_means_something),
+            ids.len() < global.len()
+                || global.iter().all(|op| local_means_something(op.as_ref())),
             "the filter dropped nothing, so either it is not running or the \
              chain has nothing left that a layer cannot carry"
         );