Yolop 0.18.2 release

Highlights

• Setup validates provider auth before completing model selection (#709)
• CLI attaches through shell descendants so managed sessions stay reachable (#711)
• Muse xhigh is accepted on cold startup (#712)
• README rewrite and control-plane docs keep the public surface accurate (#707, #715)

See the GitHub release and the full release notes for every pull request in this version.