couchpotatoserver: remove bottle :unneeded and use service

[cho-m]

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Extracted from #79995 to independently check on audit failure.

[cho-m]

I think we can bottle this once #79366 is merged, which will remove the plist.

@SMillerDev Is the service block bulk PR close to merge?

If not, it may be worth just extract changes for couchpotatoserver into this PR since we are close to finishing up #75943

[SMillerDev]

Go for it, I'll rebase.

[BrewTestBot]

🤖 A scheduled task has triggered a merge.

[carlocab]

Looks like this ships a pre-compiled unrar in libexec/libs/unrar:

❯ file couchpotatoserver/3.0.1/libexec/libs/unrar2/unrar
couchpotatoserver/3.0.1/libexec/libs/unrar2/unrar: Mach-O executable i386

We should just get rid of that. It doesn't even work on any system we support. Indeed:

❯ ./couchpotatoserver/3.0.1/libexec/libs/unrar2/unrar
zsh: bad CPU type in executable: ./couchpotatoserver/3.0.1/libexec/libs/unrar2/unrar