chore: bump default ISM max depth from 5 to 7 (#3989)

### Description

Needed for some Renzo messages that hit the max depth

### Drive-by changes

- drive by to update the agent config with the updated registry

### Related issues

<!--
- Fixes #[issue number here]
-->

### Backward compatibility

<!--
Are these changes backward compatible? Are there any infrastructure
implications, e.g. changes that would prohibit deploying older commits
using this infra tooling?

Yes/No
-->

### Testing

<!--
What kind of testing have these changes undergone?

None/Manual/Unit Tests
-->

rust/agents/relayer/src/msg/metadata/base.rs

@@ -278,8 +278,9 @@ pub struct BaseMetadataBuilder {
     allow_local_checkpoint_syncers: bool,
     metrics: Arc<CoreMetrics>,
     db: HyperlaneRocksDB,
-    max_depth: u32,
     app_context_classifier: IsmAwareAppContextClassifier,
+    #[new(value = "7")]
+    max_depth: u32,
 }
 
 impl Debug for BaseMetadataBuilder {

rust/agents/relayer/src/msg/processor.rs

@@ -452,7 +452,6 @@ mod test {
             false,
             Arc::new(core_metrics),
             db.clone(),
-            5,
             IsmAwareAppContextClassifier::new(Arc::new(MockMailboxContract::default()), vec![]),
         )
     }

rust/agents/relayer/src/relayer.rs

@@ -242,7 +242,6 @@ impl BaseAgent for Relayer {
                     settings.allow_local_checkpoint_syncers,
                     core.metrics.clone(),
                     db,
-                    5,
                     IsmAwareAppContextClassifier::new(
                         mailboxes[destination].clone(),
                         settings.metric_app_contexts.clone(),