UPX the binary so it would save bandwidth

especially for 3rd world countries where internet is slow
```
upx pkl
Ultimate Packer for eXecutables
Copyright (C) 1996 - 2020
UPX 3.96 Markus Oberhumer, Laszlo Molnar & John Reiser Jan 23rd 2020

File size Ratio Format Name
-------------------- ------ ----------- -----------
87137256 -> 26604364 30.53% linux/amd64 pkl

Packed 1 file.
```

Start by locating how the pkl Linux/amd64 binary is built and distributed, then check whether UPX can be incorporated into that process. Compare the current 87 MB artifact with the reported packed size and verify that the resulting binary remains usable before considering the work done.

Written by the indexing model from the issue text.