chore(release): v0.18.2 (#276)

Three commits have been sitting unreleased on main, two of them the same
trap seen from both ends: an install that succeeds into the wrong home.

  #272  install.sh refuses `sudo curl … | sh` up front, before the
        download, instead of writing the payload into /root/.moshcode
        where the user who typed the command cannot read it.

  #274  `dns` escalates itself per command rather than telling the
        operator to `sudo moshcode …` — advice that was right for dns
        and dangerous for `update`, which self-updates through the
        installer and so reinstalls into root's home.

  #273  the /prd healthy-cwd test no longer launches a real engine; the
        suite went from 479s to ~70s.

Co-authored-by: Claude Opus 5 <noreply@anthropic.com>

Author: ralyodio

package.json

@@ -1,6 +1,6 @@
 {
   "name": "moshcode",
-  "version": "0.18.1",
+  "version": "0.18.2",
   "type": "module",
   "description": "moshcode — a metal wrapper for coding engines and native UGig/CoinPay workflow CLIs, with OpenPRD and moshscript",
   "bin": {