fleet(queue): fleet queue --version / repo-queue --version silently ignore trailing arguments

Summary

The queue domain's --version shortcut in the fleet multicall binary checks only the first argument and returns success no matter what follows it:

• pkgs/fleet/crates/fleet/src/main.rs:458-475 (run_domain, #[cfg(feature = "queue")] arm): when args.first() is --version or -V, it prints the version and returns EXIT_OK — args[1..] is never inspected.
• The root built-ins in the same file got exactly this fix in fleet: root built-ins (version / capabilities / --version) silently ignore trailing arguments #5572: run_root's --version/-V/version/capabilities arms all call reject_extra_args first (main.rs:661-682), and the queue client's own verbs got the same treatment in fleet(queue): repo-queue silently ignores extra positional arguments on every verb #5592. The domain-level shortcut that sits in front of the queue client is the one surface both fixes missed — it intercepts the invocation before fleet_queue::client::run(args) is ever reached.

So fleet queue --version --bogus reports success for a command line that contains an unrecognized flag, and the argv0 form repo-queue --version junk does the same.

Verified this run (2026-11-04, laptop, binary rebuilt from main 18f0aa1a6)

$ fleet queue --version            → "fleet 0.1.0", exit 0   (control, correct)
$ fleet queue --version junkextra  → "fleet 0.1.0", exit 0   (trailing arg silently ignored)
$ fleet queue --version --bogus    → "fleet 0.1.0", exit 0   (unrecognized flag silently ignored)
$ fleet queue -V junk              → "fleet 0.1.0", exit 0   (same for -V)
$ repo-queue --version junk        → "repo-queue 0.1.0", exit 0  (argv0 alias route, same arm)
$ fleet --version junk             → usage error, exit 2     (control: root arm, fixed by #5572)

Why it matters

• A version probe in a script or CI step that accidentally appends an argument (or a caller who mistypes a flag) gets a clean success and a version string instead of the usage error every sibling surface now returns — the exact silent-misparse class fleet: root built-ins (version / capabilities / --version) silently ignore trailing arguments #5572/fleet(queue): repo-queue silently ignores extra positional arguments on every verb #5592/fleet: serve <broker-role> silently ignores all trailing arguments — a typo'd flag starts the daemon instead of erroring #5568/fleet: proxy serve --help (and any trailing argument) silently starts the session-proxy daemon #5575 have been eliminating across the fleet surfaces one leaf at a time.
• The shortcut is also the argv0 repo-queue binary's only version surface (the census fix noted in the arm's own comment), so the laxity ships in two binaries' shapes from one arm.

Acceptance criteria

• fleet queue --version <anything-else> and fleet queue -V <anything-else> (including via the repo-queue argv0 alias) exit 2 with a usage error naming the unexpected argument, before printing the version — mirroring run_root's reject_extra_args behavior for the root built-ins.
• Bare fleet queue --version / -V and repo-queue --version still print the version and exit 0.
• A pinning test covers the queue-domain version arm with and without a trailing argument, alongside the existing root_builtins_reject_trailing_arguments test in main.rs.

Evidence

• pkgs/fleet/crates/fleet/src/main.rs:458-475 (unguarded queue-domain version arm), :661-682 (root arms with the reject_extra_args guard), :626-639 (reject_extra_args itself)
• Probe: fleet binary rebuilt on the laptop from main 18f0aa1a6 (2026-11-04), outputs above
• Related: fleet: root built-ins (version / capabilities / --version) silently ignore trailing arguments #5572 (root built-ins, closed), fleet(queue): repo-queue silently ignores extra positional arguments on every verb #5592 (repo-queue client verbs, closed), epic: one fleet multicall binary — search, queue, dispatch, proxy — with capability-selected builds #5412 (fleet multicall epic, open)