[Bug] Proxy gRPC queryRoute stops processing queues after a missing broker entry

### Problem

`RouteActivity#queryRoute` stops iterating all queue data when one queue row has no matching broker entry in the built broker map.

Current code:

```java
Map brokerIdMap = brokerMap.get(brokerName);
if (brokerIdMap == null) {
break;
}
```

Because this uses `break`, a single malformed or stale `QueueData` entry can truncate the whole route response and hide later valid queues.

### Expected behavior

A missing broker entry should only skip that malformed queue row. The proxy should continue processing remaining queue rows that still have valid broker mappings.

### Impact

This can produce partial or empty gRPC `QueryRoute` responses when route metadata contains a stale queue row before valid rows. That affects Proxy/gRPC route discovery and can make clients miss usable queues.

### Suggested fix

Change the missing broker-map path from `break` to `continue` and add a regression test with:

- one queue row whose broker name is absent from `brokerMap`
- one later queue row with a valid broker mapping
- assertion that the valid later queue still appears in the query route response

Start at RouteActivity#queryRoute and trace how brokerMap and queue data are processed. Add the regression test described in the issue, then verify that a later queue with a valid broker mapping still appears in the gRPC QueryRoute response after an earlier missing mapping.

Written by the indexing model from the issue text.