Also scan swirlds.log in CI `LogValidationTest`

### Problem

We will miss any exceptions propagated into a platform `catch` unless we scan _swirlds.log_ at the end of CI.

### Solution

Update `LogValidationTest` to do this.

### Alternatives

_No response_

Start by locating LogValidationTest and its existing CI log-validation checks. Review how the current logs are selected, then include swirlds.log in the same validation; done when CI catches exceptions written there.

Written by the indexing model from the issue text.