Class stat

src/watcher/watcher.c:500–500

/* Platform-portable mtime_ns (mirrors pipeline_incremental.c). */
static int64_t sig_stat_mtime_ns(const struct stat *st) {
#ifdef __APPLE__
    return ((int64_t)st->st_mtimespec.tv_sec * NS_PER_SEC) + (int64_t)st->st_mtimespec.tv_nsec;
#elif defined(_WIN32)