Update libsodium to 1.0.9 - #1

Changes:
* No longer automatically upgrades all your packages by default. You can regain
this behaviour by passing `--upgrade` to the command.
* Default behaviour is to now run `brew update` once every 24 hours.
* You can now access the command summary by passing `--help` or `-h` as well as nothing.
* Added versioning to make it slightly clearer when the autoupdate command changes.

Future plans:
* Ability to pass specific formulae to the command so you can upgrade those automatically & selectively.
* Ability to choose how often the autoupdate is run. 24 hours will remain the default, but choice is good.

Welcome ideas on improvement if you have any specific requests/ideas/etc.

Closes Homebrew#1.

Two related regressions in 1.0.0 prevent `container system start` from
completing:

1. The previous formula patched
   Sources/ContainerPlugin/InstallRoot.swift via `inreplace` to hard-code
   the keg prefix as the install root. Upstream PR apple/container#1558
   (May 2026) renamed the symbols the inreplace targeted
   (`CommandLine.executablePathUrl` ->`executablePath`,
   `deletingLastPathComponent` -> `removingLastComponent`), so the
   substitution silently became a no-op when 1.0.0 was bumped. The
   apiserver now resolves its install root as the lexical grandparent of
   the running executable without symlink resolution, which on
   /opt/homebrew/bin/container lands at /opt/homebrew rather than the
   keg, where no `libexec/container-plugins` directory exists. The
   apiserver crash-loops with "cannot find any plugins with type
   network" and `container system start` hangs at "Testing access to
   container-apiserver...".

   Fix this without patching upstream sources by installing the binaries
   to libexec/ and using `bin.env_script_all_files` to generate shim
   wrappers in bin/ that `exec` the real binaries via their absolute
   keg path. The kernel-reported executable path now has `opt_prefix` as
   its lexical grandparent, putting the plugin search exactly on top of
   `opt_prefix/libexec/container-plugins/`. The wrappers also export
   `CONTAINER_INSTALL_ROOT=opt_prefix` for the code paths that honor the
   environment variable.

2. The 1.0.0 release added a new `machine-apiserver` plugin
   (apple/container#1662, "container machine") under
   Sources/Plugins/MachineAPIServer that the formula never picks up.
   `container system start` fails at the "Verifying machine API server
   is running" step without it, so it must ship together with fix Homebrew#1
   for the start command to succeed at all.

Refactor the plugin installation loop to a data-driven structure so
adding the new plugin (with its config.toml plus init and
create-user.sh resources from Sources/Plugins/MachineAPIServer/Resources/)
is a one-line addition. Codesigning mirrors what the upstream Makefile
does for that binary (--prefix only, no entitlements; no
`signing/machine-apiserver.entitlements` exists upstream).

Verified locally with:

  brew install --build-from-source container
  brew test container
  brew audit --strict container
  container system start
  container list
  container machine list