feat: add Existence/runtime-validity bug-class to adversarial-design-review (#55)

[intel352]

Summary

Adds one Existence / runtime-validity bug-class to the adversarial-design-review design-phase checklist (inherited by the plan phase via SKILL.md:101), closing a 2-retro gap where a review verified an artifact's intended content but never that the artifact exists or runs as the design assumed. Releases as v6.2.2.

Closes #55.

Design

See: docs/plans/2026-05-31-existence-runtime-validity-bugclass-design.md (design-phase adversarial review PASS at cycle 2: cycle 1 = 0C/2I/3m all resolved; cycle 2 = 0C/0I/1m applied).

Implementation Plan

See: docs/plans/2026-05-31-existence-runtime-validity-bugclass.md (plan-phase adversarial review PASS = 0C/0I/3m all applied; alignment-check PASS; scope locked).

Scope Manifest

• PR Count: 1
• Tasks: 3
• Status: Locked 2026-05-31T22:07:47Z
• This PR (row 1): Task 1, Task 2, Task 3 — branch feat/existence-runtime-validity-bugclass-55

Changes

• Task 1 — skills/adversarial-design-review/SKILL.md: one new design-phase row. (a) For any artifact a design edits but did not create, require an ls/gh existence check before mutation (the required_secrets sweep hit a missing workflow-registry manifest at execution). (b) For any artifact a design emits, require verifying the consumer surface is real (smart-CI gen emitted wfctl ci run --phase migrate, no such phase). Explicit Clean escape hatch for designs that neither edit nor emit a consumed artifact. Row count 19→20.
• Task 2 — RELEASE-NOTES.md: v6.2.2 entry.
• Task 3 — version bump 6.2.1→6.2.2 across .claude-plugin/plugin.json, .claude-plugin/marketplace.json, .cursor-plugin/plugin.json (merge to main auto-triggers release-tag.yml).

Verification (evidence)

• grep -c "^| \*\*" skills/adversarial-design-review/SKILL.md → 20 (was 19); awk confirms row sits in the design-phase section.
• bash tests/skill-content-grep.sh → PASS (host-neutral; wfctl/gh/ls/workflow-registry are not forbidden tokens).
• bash tests/version-check.sh → OK: All version files agree on version 6.2.2.
• bash tests/plan-scope-check.sh --verify-lock → PASS (manifest hash intact).
• skill-cross-refs / skill-compression-notes → PASS.
• Two-stage review (spec + quality) → APPROVED.

Note

Copilot review intentionally not requested (Copilot review broken). Merge gate = adversarial-review clean + CI green.

Generated by the implementing agent.