self-upgrade

# Self Upgrade Per toprank pattern: 9-step upgrade with dev-symlink detection. ## Workflow ``` 1. Log start to ~/.xuanran-seo/upgrade-log.json 2. Detect install dir + check for dev-symlink (skip upgrade if dev mode) 3. Save current version + state to /tmp/xs-upgrade-backup/ 4. git fetch origin main + git reset --hard origin/main in marketplace clone 5. rsync to versioned cache dir 6. Update ~/.claude/plugins/installed_plugins.json: - new installPath - new version - new gitCommitSha 7. Purge old cache (keep only latest 3 versions + dev) 8. Parse CHANGELOG.md between old and new versions → 3-7 bullets 9. Write ~/.xuanran-seo/just-upgraded-from = old_version Clear ~/.xuanran-seo/last-update-check Resume original skill that triggered upgrade ``` ## Entry points - Inline: `bin/update-check` returns `UPGRADE_AVAILABLE x.y.z` → auto-trigger - Standalone: `/upgrade` command ## See also - `bin/update-check` - `bin/preamble.md` (consumed UPGRADE_AVAILABLE signal)