feat(kmutil): add completion spec

[ump45nose]

Closes #937

Adds a completion spec for kmutil, the Apple kernel-extension/collection management tool
(kmutil(1) on macOS 11+).

The spec covers the shared options (--variant-suffix, --arch, --no-authorization,
--verbose, --help), the extension/collection selectors (--bundle-path,
--bundle-identifier), and the subcommands check, clear-staging, create,
find, inspect, install, list, load, logs, showloaded, stat, unload,
uninstall, dumpstate, help and print-diagnostics.

Every option and subcommand name and description was taken from kmutil help,
kmutil <subcommand> help and the kmutil(1) man page, so nothing is invented.

Testing: npx tsc --noEmit on src/kmutil.ts succeeds, and yarn run lint reports no new
findings. I cannot launch the Fig client on this machine, so the spec was not exercised
end-to-end in a shell.

This pull request was prepared with the assistance of an AI coding agent and has not yet
been reviewed by a human.

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[withfig-bot]

Overview

src/kmutil.ts:

Info:

[withfig-bot]

Hello @ump45nose,
thank you very much for creating a Pull Request!
Here is a small checklist to get this PR merged as quickly as possible:

• Do all subcommands / options which take arguments include the args property (args: {})?
• Are all options modular? E.g. -a -u -x instead of -aux
• Have all other checks passed?

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