v2.2.0: Triage skill renamed; batched, measured clustering

• Skill feedback-triage is now agent-feedback-triage 2.0. The
  invocation name and the install directory change: update installers,
  links and prompts that name skills/feedback-triage, and remove the old
  copy (operate.md lists both names). Digests move to
  ${TMPDIR:-/tmp}/agent-feedback-triage/. No service/API or storage changes.
• The triage skill is direct invocation only: disable-model-invocation: true
  (Claude Code) and a description that forbids loading it from phrasing
  about the queue. Invoke it as /agent-feedback-triage or by name.
• Docs: install guidance for the triage skill, the rule to re-measure after
  any cluster.py prompt, threshold or batching change, and the eval
  script's disclosure boundary in security.md.
• cluster.py batches comparisons: up to 8 reports per request, every pair
  asked once over a shared state, so 24 reports need 15 requests instead of
  276 (which exceeded the old cap and skipped advice). One request per pair
  remains the fallback for batch sizes below 4 and for chunks over the
  model's token budget; a pair too large alone is marked unassessed without
  a request. One invalid answer in a batch marks only that pair.
• --max-pairs is replaced by --max-requests (default 200); the old
  flag is rejected because its unit changed. New --batch-size (default 8).
• Probability sums tolerate the model's per-option two-decimal rounding.
• Calibration recorded in the skill: on 112 labelled pairs, no different
  pair was grouped at the 0.8 threshold; consent, dry-run, key handling and
  complete-link grouping are unchanged. scripts/eval-cluster.py repeats
  the measurement and refuses to send any report whose exact remote was not
  approved with --allow-repo.
• Go module dependency updates (indirect only).