invocation-mode: grade session-flow:show-options against the exception classes (post-dates the lane 8 fleet grade)

[kyle-sexton]

Context

Course lane 8's fleet grade (docs/conventions/invocation-mode/README.md § Fleet grade, 2026-08-17) examined the non-setup disable-model-invocation: true skills against the rubric's three exception classes. session-flow:show-options landed 2026-08-18 (b3e7af72), a day after that grade, so it was never in the graded population — the ADR 0005 bound scopes the grade to the question asked at that date, not to skills added later.

Surfaced during #2969 (PR #3023) by an automated reviewer: a post-flip recount showed 10 non-setup true skills against a table carrying 9 verdicts. The gap is now recorded in the rubric doc rather than left implicit, and this issue carries the grading.

skill-quality:check check 24 (shipped in #2968) does not fail this — a non-setup true gets a hand-verify note, precisely because class attribution is not machine-checkable.

Proposed work

• Grade session-flow:show-options against the rubric's three exception classes: (i) side-effect / manual-timing workflow, (ii) setup skill, (iii) maintainer-only.
  • Its stated job is laying out fitting skills as a decidable, nothing-hidden menu for the human to choose from. Note the rubric's router-skill verdict (REJECTED, 2026-08-17): a model-invoked skill that routes the agent to user-invoked skills is rejected for this fleet, with a carve-out for domain-scoped composition routers. Whether show-options is that rejected pattern, the admitted carve-out, or a class-(i) deliberate-mode-entry is exactly the question to settle — do not assume the answer from its current true.
• Either add its row to the fleet-grade table with a class and KEEP verdict, or flip it to false if no class fits (the planning: flip questionnaire to model-invoked — the one invocation-mode re-grade flip #2969 precedent).
• Update the post-flip counts paragraph so it no longer names an ungraded skill.
• Version bump + CHANGELOG entry if the skill's frontmatter changes.

Acceptance criteria

• session-flow:show-options carries a recorded verdict in docs/conventions/invocation-mode/README.md (a class + KEEP true, or a flip to false)
• The rubric doc's non-setup count no longer refers to an un-attributed skill
• Version bump + CHANGELOG entry if the skill changed

References

• docs/conventions/invocation-mode/README.md (the rubric and its fleet grade)
• skill-quality/plugin-philosophy: aihero course lane 8: invocation-mode doctrine and evidence-driven fleet re-grade #2910 (lane 8 specification), skill-quality/fleet: enforce the invocation-mode rubric — explicit disable-model-invocation on 17 skills, check criterion, skill-authoring pointer #2968 / PR feat(skill-quality): enforce the invocation-mode rubric fleet-wide #3021 (check 24), planning: flip questionnaire to model-invoked — the one invocation-mode re-grade flip #2969 / PR feat(planning): make questionnaire model-invoked #3023 (the one prior flip)
• plugins/session-flow/skills/show-options/SKILL.md