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In increasing order of difficulty:
Write "Leave On" on tape on the switches. What, really, are you worried about? This gives you 99.9% of the result for 0.1% of the effort.
Install switch covers.
Install key- or code- operated switches.
Do something James-Bondy like put in Smart Switches and code the hub to respond to their being turned off ...
6
You can buy key-operated wall switches like this. I think they tend to be called 'fish key' operated, due to the shape of the flat metal key / operating implement. I have one installed on my LED lighting in an otherwise dark and forbidding corridor.
The lock is not a security level lock (though you can get these as well), it's just not possible to ...
2
You want to be able to turn off the light for safety should you need to replace the bulb. You might do that by using the circuit-breaker, but that will turn off all the ceiling lights on that floor.
The cheapest approach is a bit of tape over the switch "do not turn off", or put a bit of work into making a more attractive "Molly guard"
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