Programming ESP32 MCUs for production
Yes. Most manufacturers would just require a binary (or HEX depending on MCU) file of your compiled code. If it's not a system they already know how to handle you will also need to provide a procedure for them to follow to program the device. What form that takes depends on the manufacturer.

You can also generally order pre-programmed MCUs and modules direct from the manufacturer where they (for a small fee) will program the chips for you before they are then sent to the board manufacturer for population.

If there is no facility on the MCU manufacturer's website then just email their sales department and I am sure they would be happy to quote you. Again, all they will require is a HEX or BIN file (depending on manufacturer) for programming.