v1.12.0

Added

• Plugin bundles now auto-detect hosts and upgrade only on version change. The
  harness plugin phase (the root install.sh k) harness menu,
  scripts/setup-local-first.sh, scripts/install-harness.sh --plugins) detects each agent host — its config dir
  exists or its binary is on PATH — and installs only detected hosts; absent hosts
  produce one skip log line and no filesystem writes. Every successful plugin install
  records the bundle version and an ISO-8601 timestamp in
  ~/.config/massa-ai/install-state.json (a v2-compatible extension that
  install-skills.sh round-trips but never writes): re-runs at the same version are
  no-ops, older recorded versions upgrade automatically, newer ones are never
  downgraded, and a host whose installer fails records nothing and never aborts the
  remaining hosts. --dry-run reports the per-host decision (install / upgrade /
  skip-current / skip-absent) without writing anything, and --uninstall removes the
  version record while keeping its existing semantics (whole-record delete only for
  plugin-owned platforms). Direct apps/<host>-plugin/install.sh --user installs
  behave exactly as before, plus the same version recording.