chore: declare a model and effort for each agent skill stage

[V3RON]

Closes #109

What changed

Each agent stage now runs on its declared model and effort, whether work-issue delegates it, a person types it as a slash command, or another agent loads it. Review, triage, design and memory stages fork on opus at high effort. implement-issue forks on sonnet at medium, and e2e-device on sonnet at low. file-issue (sonnet, medium) and cut-release (sonnet, low) stay inline because they need the conversation. work-issue now invokes each stage's skill directly through the Skill tool, with the task as arguments. It no longer starts a general-purpose agent to load the skill, and it never passes a model. The Skills table in AGENTS.md gains Model, Effort and Forked columns, and the table says to change them together with the frontmatter. The mapping follows the issue's amended table, including the effort addendum.

Acceptance criteria

#	Criterion	Test	Tier
1	Every skill's frontmatter matches the table (model, effort, fork)	Checked against the amended table	manual
2	AGENTS.md Skills table has Model, Effort and Forked columns matching the frontmatter	Checked against the frontmatter	manual
3	CI check for drift	Dropped at the maintainer's request: drift can't break anything silently	—
4	work-issue invokes each stage with the Skill tool and arguments and still gets the report block	Probes below: each fork returned its skill's report-block first line to the caller	integration
5	Headless runs prove the routes	Probes below	integration

Headless probes, Claude Code 2.1.281, claude -p … --output-format json in this branch. Bash, Edit, Write and Agent were disallowed. Each probe asked the forked skill to echo a nonce from its arguments and then stop.

Session	Route	modelUsage / effort	Fork's reply
--model sonnet	Skill tool → review-pr	claude-sonnet-5 (caller) + claude-opus-5-5 (fork)	N7Q2 claude-opus-5-5 PR: #N Verdict: approve | comment | request-changes
--model opus	Skill tool → implement-issue	claude-opus-5-5 (caller) + claude-sonnet-5 (fork)	K4M9, Sonnet 5 (claude-sonnet-5), Branch: issue-N-slug PR: #M (draft)
--model sonnet --effort high	Skill tool → e2e-device, PreToolUse hook logging effort	caller's Skill call: high; fork's Read call (agent_type: general-purpose): low	PROBE E5T1 + Target(s): <list> Commit: <sha>

The nonces (N7Q2, K4M9, E5T1) show that each forked skill received the arguments it was invoked with.

E2E evidence

Not applicable. This changes agent tooling only.

Checklist

• CHANGELOG.md has an entry under Unreleased (writing-changelog skill), or the change is not user-visible
• User-facing docs updated for every surface the change touches (writing-user-docs skill), or the change is not user-visible
• No new import past a module's index.ts; no new direct node:* I/O outside an adapter
• Simplification checklist from the architecture skill applied, exceptions explained above
• docs/ARCHITECTURE.md updated if a surface it describes changed

Out of scope

• The branch is claude/elegant-hamilton-l2yerq, not issue-109-<slug>, because this session had to push to that branch.
• The review and E2E stages were skipped at the requester's direction. This PR has had no agent review.

Status

Implement: done (4/4, criterion 3 dropped) Review: skipped (by request) E2E: not applicable Ready: yes

🤖 Generated with Claude Code

https://claude.ai/code/session_01WwCFb6cH1WSzCS8iob6A7e