Here is a simple switched shutdown circuit I built with minimal parts from a basic electronic kit. You have to use the code from another project to make it work but its very simple and cheap to build.
with flip of switch , the software shuts down and then the power to the pi is cut after.
see attached image, it explains it all and can be built in bout n hour or less.
hope you guys like it.
btw, this is a off label way to use a 555 timer, but cuts out a lot of other parts you would need to achieve same. but works great!
details are in the img attaced
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