According to https://xkcd.com/221/ the random number should be 4 :-)
In reality a randomizer will just be an algorithm to create numbers and often they get initialized by a timer. So if you always start the same code after reset and read the number it seems to met always the same initialisation. I miss a function to "randomize" the initialisation. Try to do it by any loop/function before that delays in a random way e.g. connection to wifi or read from a noisy AD channel until a specific value is read.

Theoretically yes. It depends on how good your training data set is and the light situation where the classification is done. Keep in mind the camera has a limited resolution.

I don't know the exact specs and I have not tested. In my oppinion the battery will be the weak point. The small LiPo bag-batteries often go very weak below 0°C. You may remove it and power from external.
The datasheet of the image sensor OV2640 says operating is allowed between -30°C and +70°C, stable image between 0°C and 50°C. for the other components you can find similar information in their data sheets.
Make sure there is not too much humidity in air as it can condense on the electronic parts.
It may help to pack the camera into thermal insulation so that it heats itself a bit over the environment. In extreme environment a small extra heating could help.

the board in your link seems to have PSRAM but in the code the selected model has "No PSRAM".

Did you ever think about multiplexing? One Header as Serial I/O and one as 2-Bit control for an external 1:4/4:1 MUX. The SN74LV4052A for example provide two1:4 paths. You can use one for the RX, one for the TX signals.
Your program need to select the channel by two bits and then do the normal UART stuff as usual.

This is not an Uiflow specific solution. Try as following:

• Decide how many steps you want from start color to end color. e.g. 10 steps
• find the step size from start to end color e.g. you want from value 100 to 200 (difference / steps) = step size 10.
• loop for the number of steps and increase/decrease the value with the calculated step size.

some USB to UART chips such as the CP210x family are customizable by the device manufacturer to have its VID and / or PID.
See: https://community.silabs.com/s/article/cp210x-customization?language=en_US
In this case you need also a cusomizated driver or telling the existing driver the new VID/PID (which is possible for example in a linux environment). It is no problem to have several drivers in parallel as they only work for devices with the correct VID/PID.

I assume you have changing text in the label. For the Y-axis set the label manually to the half of screen height minus the half of label height. The X-axis can be calculated by using half of screen width and half of label width label0.get_width().

the IP Adress is not hard coded when using DHCP to obtain it. Do you mean the hardware MAC adress? It is (theoretical) unique on every piece of network hardware.
WiFi.macAddress()

You can use the "Device File Manager" in UiFlow.