support apple silicon and reconstruction code

[xiehuc]

original xkbswitch-macosx's code is full of bug and hard to understand.

for eample:

it use input source list index as an id, makes id differs on
different machine
it show layout by hard code it. just couldn't know why
it couldn't set im.rime.inputmethod.Squirrel.Rime because it believes
every sourceid has an com.apple prefix and hard code it.
so i modify it (copy from https://github.com/minoki/InputSourceSelector,
change api, which earlier and better)

[jdhao]

@xiehuc thanks, this works perfectly for mac with M1 cpu.

[xiehuc]

you are welcome, my repo have pre build binary.

[yunake]

this is excellent! thank you, clean code, clean build, works like a charm on my m2

[Sharpieman20]

Thanks so much for this, saved me a lot of time trying to figure this out.