Optimize payload

[OverkillGuy]

There are multiple improvements to make to payloads to reduce the number of chunks to scan, and possibly generate codes faster too.

• Avoid base64 encoding by using binary-mode QR codes, removing the 34% overhead.
• Bigger payload size, increasing QR codes size (called "version" in QR code jargon) up to "version 40", which can pack ~3KB, a x3 increase
• Compressing the file (zstd) to make payload smaller
• Configurable error correction, to increase number of payload bytes vs error-correction ones (dangerous)

I include as part of this effort making payload size adjustable, so we can choose to have many small QR codes instead of a small number of big ones