Add a new `atClone()` method to the simulation core and expose it through all language bindings.
This method is intended to be called in a child process after a fork() to re-initialize the state of the Verilated model. This is crucial for supporting robust multi-process simulation environments, such as Python's `multiprocessing`, where forking can lead to an inconsistent state in the simulator's child instances.
Additionally, this commit includes several stability and memory management improvements:
- Fix memory leaks in `DutUnifiedBase` and the C++ wrapper by ensuring allocated resources are properly deallocated.
- Add a null-pointer check in `FlushWaveform` to prevent crashes when a waveform dumper is not present.
- Expose the `atClone` functionality to C++, Go, Java, Lua, Python, and Scala wrappers.
Makiras
yaozhicheng