Consolidate skill/plugin commands in `clawhub` cli

Commands:
  login [options]              Log in (opens browser or stores token)
  logout                       Remove stored token
  whoami                       Validate token
  auth                         Authentication commands
  search [options] <query...>  Vector search skills
  install [options] <slug>     Install into <dir>/<slug>
  update [options] [slug]      Update installed skills
  uninstall [options] <slug>   Uninstall a skill
  list                         List installed skills (tracked and manually installed)
  explore [options]            Browse latest updated skills from the registry
  inspect [options] <slug>     Fetch skill metadata and files without installing
  publish [options] <path>     Legacy alias: publish a skill from folder
  delete [options] <slug>      Soft-delete a skill (owner, moderator, or admin)
  hide [options] <slug>        Hide a skill (owner, moderator, or admin)
  undelete [options] <slug>    Restore a hidden skill (owner, moderator, or admin)
  unhide [options] <slug>      Unhide a skill (owner, moderator, or admin)
  skill                        Manage published skills
  package                      Browse and publish OpenClaw packages
  transfer                     Transfer skill ownership
  star [options] <slug>        Add a skill to your highlights
  unstar [options] <slug>      Remove a skill from your highlights
  sync [options]               Scan local skills and publish new/updated ones