refactor(cpn): sort custom functions list

[elecpower]

Satisfies Companion side of #3591

[elecpower]

@pfeerick no reason this cannot be merged without the radio side is there?

[pfeerick]

Yes, and no? Didn't we want radio and companion to match (oh wait, maybe this is deserved since Companion gets left behind?) 🤪 Companion lists them mostly in the same order as the radio atm, but radio side is going to be a pain (since we can't just sort it like with Companion 😢 ), so probably better to merge this than leave it in limbo any longer.

[philmoz]

One option for the radio is a sorted index table for each language translation.
It would not add much to the firmware size (compared to locale handling), and could potentially be auto-generated.

[pfeerick]

That's the only really viable option I can see, since it's the index we really need sorted (for it to just work for all UIs)... as I think doing the locale sort would have at best only worked on colorlcd? Without a major re-write to how it is SF/GF are handled for that part of the UI, that is 🤕