Agent Plugins 0.9.1

Agent Plugins 0.9.1

• Pin ESS 0.22.1 instead of 0.20.0. ESS 0.22.0 had no archives because its own release gate
  was red at the tag; 0.22.1 is the release cut with that gate green and its Release run
  publishing the four archives and SHA256SUMS. The install page, the README and the expected
  ess --version line follow.
• The ESS skill's example is re-validated on ESS 0.22.1 — the same line, warehouse v1 — 2 file(s), valid, exit 0 — and its --path paragraph no longer has to distinguish the pinned
  release from ess-inputs.yaml, which the pinned release reads.
• Align the golden path's model-driving command with Metaharness and label its older recorded
  CLI output separately from current installation requirements.
• Unlike 0.9.0, this release ran task check and task site-build on the tagged tree.