chore(admin-cli): realign straggling commands onto Dispatch + Run

[chet]

The admin CLI already has a clean two-trait story for running commands --
Dispatch on a command group (derived, so the compiler forces every variant
to be runnable) and Run on each leaf -- but a handful of commands grew up
outside it: some hand-roll their own Dispatch, a couple skip Run entirely,
and the two biggest subtrees (mlx and measured-boot) thread their own context
structs through bespoke cmds::dispatch fns. This pulls them all back onto the
traits so there's exactly one way a command runs, and the derive does the
enforcing.

What this involves

• ping, version: add the missing impl Run -- today they hand-write
  Dispatch and skip Run, unlike inventory/jump/generate-*.
• A shared bridge: a tiny dispatch_via_run! macro in cfg/dispatch.rs,
  routing the seven subcommand-less top-levels (inventory, jump, ping,
  version, generate-docs, generate-man, generate-shell-complete)
  through it -- deleting seven copies of the same impl Dispatch { self.run() }.
• scout_stream: hand-written impl Dispatch -> #[derive(Dispatch)],
  with an impl Run per leaf; drop the local CliContext.
• mlx: convert MlxAction + its six subcommand enums to
  #[derive(Dispatch)], give every leaf impl Run, retire the custom
  CliContext (just &api_client + &format, both on RuntimeContext).
  Keep the shared table/print helpers in mlx/mod.rs.
• measured-boot: same across its six subgroups; retire CliData /
  GlobalOptions, preserving the one-time set_summary(!extended) side-effect
  at the group dispatch point.
• Naming: rename the single-command cmds.rs -> cmd.rs to match the ~254
  other leaves. Leave genuinely-plural cmds.rs (mlx/, measured_boot/,
  redfish, rms, debug_bundle) alone.
• Exempt by design: redfish and rms run before the API client exists
  (own BMC/RMS clients from raw CliOptions, never see RuntimeContext), so
  they stay outside the trait flow -- main.rs already special-cases them.
  A code comment will say so.
• No behavior change: clap surface, help, and output identical;
  cargo make check-cli-docs should be a no-op.

Follow-up: once every group is on the derive, a custom lint/test could ban any
hand-written impl Dispatch, making the traits truly mandatory.