Use 'std::chrono first' approach for timer methods (like QObject::startTimer, QTimer, QDeadlineTimer etc.)

As discussed here (The discussion on this topic is still open, and this task may be rejected, so far, this task is only a placeholder to track the progress of the work )

Change the API of all methods representing time from int/qint64 to std::chrono::milliseconds, this allows:
This makes the range issues a SEP. std::chrono::millisecond isn't required to support a full 64-bit range in count(), so we'll likely have a problem with supporting the full 64-bit range at the OS level ourselves, esp. when we have to convert back, e.g. because we're calling std::condition_variable API. By using chrono-first, we move any overflows into the user's code and our functions can be noexcept. ~ mmutz

Follow the porting guide from qsizetype epic.