daily-fix: fan-out completion contract in spawn briefs

Overview / Motivation

Auto-filed by /daily 2026-08-02 (route 2: behavior/logic change -> independent review) from the nightly problem sweep (miners 3/8, sessions 55419495/c905b084/3a60e6ee, tasks #1739/#1902).

Goal

Fan-out work products land durably (committed or consolidated) in the same turn they are produced, and delegated turns never end awaiting background work.

Workflow gap

• Bug observed: (a) Three fold/fan-out subagents in one session idled mid-delivery with work staged-but-uncommitted (fold1739, judgerel1739, ladderfold1739 -- the last idled 3x; the orchestrator committed for it and fixed a broken doc anchor it left; it had also staged an uncertified code payload that tripped the root-commit guard) (session 55419495). (b) Four lit-dive scout reports lived only in /tmp for ~11h with the synthesis chat-only, until Thomas asked 'did you save all this to a report' (session c905b084). (c) A delegated Step 10d subagent ended its one turn blocked on a background gate, orphaning its own monitor; the orchestrator had to detect and re-drive with explicit finish-synchronously instructions (session 3a60e6ee).
• Why it is a workflow gap: The same-turn completion contract binds the 9a-ter inline path and teammate REPORTS, but fold/fan-out spawn briefs do not restate it, so subagents idle with uncommitted work; and no clause makes join-time consolidation the default for multi-agent research output.
• Confidence (emitter): medium (incidents probed by miners with verbatim rows)
• verified-at-filing: grep -c -iE 'same-turn commit' CLAUDE.md .claude/skills/issue/SKILL.md -> present for the 9a-ter inline rounds; 0 hits binding SPAWN BRIEFS for fold/fan-out agents; join-time consolidation default 0 hits (item 7 covers the orchestrator's own chat analyses only).

Proposed change (refine in planning)

(i) fan-out/fold spawn briefs RESTATE the same-turn commit+push completion contract AND the inline-payload-lint-gate duty for any script the round writes; (ii) the orchestrator consolidates fan-out reports into a durable home (repo doc / vault) at JOIN time by default -- offer-to-save is the banned shape; (iii) a brief delegating a gate-wait mandates synchronous waiting (bounded foreground or Monitor until-loop inside the turn).

Scope / surfaces

• Primary target: CLAUDE.md, .claude/skills/issue/SKILL.md

Constraints / invariants

• Workflow-surface rules apply; scripts/workflow_lint.py --check-asks passes; ruff on touched files passes.
• This session runs under EPM_WORKFLOW_FIX_SESSION=1 (Provenance workflow_fix_target: line) -- it MUST NOT auto-route its own subagents' workflow-fix candidates (recursion guard).

Provenance

• sha-verify (filing-time, #1467): c905b084 cited in commit context does NOT resolve as a commit in this repo at filing time — treat as a transcript/session reference, not a commit.

• sha-verify (filing-time, #1467): 3a60e6ee cited in commit context does NOT resolve as a commit in this repo at filing time — treat as a transcript/session reference, not a commit.

• fingerprint: fcc42ef9fba9

• workflow_fix_target: CLAUDE.md, .claude/skills/issue/SKILL.md