The mutation-testing PR keeps the eventfd notification implementation inside WaitableQueue to minimize the change set.
Revisit extracting notification into a reusable non-template component in a follow-up refactoring. The extraction should preserve eventfd lifetime and move semantics, keep the PImpl-based template mutation-testing pattern working, and include dedicated tests and CI validation.
The mutation-testing PR keeps the eventfd notification implementation inside WaitableQueue to minimize the change set.
Revisit extracting notification into a reusable non-template component in a follow-up refactoring. The extraction should preserve eventfd lifetime and move semantics, keep the PImpl-based template mutation-testing pattern working, and include dedicated tests and CI validation.