Significant overhead with even super simple scripts

Describe the bug

When running an incredibly simple script, it seems to have significant overhead.

The script (see "How to reproduce") takes significant amounts of time to run (tested with both timeit and time, running with nu command and without):

$ time nu ./example.nu world                                                                                                                                                                 09/11/2023 08:48:04 AM
Hello, world!
0.06user 0.02system 0:00.08elapsed 98%CPU (0avgtext+0avgdata 29788maxresident)k
96inputs+0outputs (0major+3054minor)pagefaults 0swaps

$ time ./example.nu world                                                                                                                                                                    09/11/2023 08:49:49 AM
Hello, world!
0.06user 0.01system 0:00.08elapsed 100%CPU (0avgtext+0avgdata 29792maxresident)k
0inputs+0outputs (0major+3039minor)pagefaults 0swaps

$ timeit nu ./example.nu world                                                                                                                                                               09/11/2023 08:48:55 AM
Hello, world!
62ms 979µs 294ns

$ timeit ./example.nu world                                                                                                                                                                  09/11/2023 08:48:39 AM
Hello, world!
83ms 369µs 401ns

How to reproduce

This is the script I used to test it:

#!/run/current-system/sw/bin/nu

def main [
  name: string
] {
  echo $"Hello, ($name)!";
}

Expected behavior

Near-instant parsing and evaluation, less then current timing.

Screenshots

No response

Configuration

Additional context

No response

Start by reproducing the reported timings for the minimal example.nu script with both nu ./example.nu world and direct execution, then profile startup, parsing, and evaluation to identify the overhead. Done means demonstrating a measured reduction in startup time while preserving the script's output and behavior.