If the device needs to be powered when the switch is OFF, and the power is not much, then across the switch is mains voltage and 5 mA at 120 V is lots of power. Neon bulbs in a plastic switch toggle have been around at least 50 years. If power is needed when the switch is closed, then a pair of diodes, inverse parallel, will provide almost a volt of pulsating power. The diodes must be good for much more than the switch load, ten amps maybe, or at least 5 amps, Low PRV is OK because each diode is shunted by the other.
So what can work depends on the application.
How comfortable is the TS working with mains power house wiring?

It all boils down to no ground wire in the fitting though which I'm just going to pull one through and that pretty much solves my whole problem anyhow. And I'm pretty comfortable working on mains. I pretty much wired my own place and I maintain our workshops 3 phase equipment so it's not and issue.
PS. 230 volts on my end too.

 

It all boils down to no ground wire in the fitting though which I'm just going to pull one through and that pretty much solves my whole problem anyhow. And I'm pretty comfortable working on mains. I pretty much wired my own place and I maintain our workshops 3 phase equipment so it's not and issue.
PS. 230 volts on my end too.

OK, pulling in a neutral requires having the good fortune of having a close by point to connect to one. Grounds are different, and while more convenient usually not accepted for active power. and for small amounts of power the schemes I suggested are acceptable, usually.