fix(codex): replay legacy user-input requests as blocking

[juliusmarminge]

plan_questions/codex fails on the V2 branch tip (393d7b3): it stalls for 60 seconds and times out.

Codex 0.156 made isBlocking required on item/tool/requestUserInput. The fixture's transcript was recorded on 0.120 and doesn't have it, so the replay client rejects the request as undecodable, and the scenario waits until its deadline. Codex itself treats a missing isBlocking as true (codex-rs/app-server-protocol/src/protocol/v2/item.rs:1778 at rust-v0.156.1, with a test for exactly this legacy case). The replay normalizer already fills other fields old transcripts lack (projectId, sessionId, startedAtMs); this adds isBlocking with Codex's default.

The failing fixture is the regression test.

Verification

• OrchestratorReplayFixtures.integration.test.ts: 75/75 pass (before: plan_questions/codex failed after 60,272 ms).
• effect-codex-app-server tests: 38/38. Typecheck: no errors or warnings. Format and lint clean on replay.ts.

Found by the agent re-recording Codex fixtures on 0.156.1 (#13505).

Model: Claude Opus 5.5 (Claude Code)

🤖 Generated with Claude Code

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[macroscopeapp]

This changes how replayed inbound requests are delivered, but the PR adds no focused test for it. Could you add a replay test with a legacy item/tool/requestUserInput frame that omits isBlocking, asserting the client receives true, and one with an explicit false to verify it remains unchanged?

^{Posted via Macroscope — Effect Service Conventions}

[github-actions]

Thread transfer impact

✅ Thread transfer remains within every enforced ceiling.

ℹ️ No successful main baseline artifact is available yet. This run establishes the initial measurement.

Provider	Metric	Main baseline	This PR	Impact	PR ceiling
Codex	Total thread wire	—	4.9 KiB	—	6.8 KiB	✅
Codex	Thread snapshot wire	—	3.7 KiB	—	4.9 KiB	✅
Codex	Live turn WebSocket wire	—	1.2 KiB	—	2.0 KiB	✅
Codex	Live turn WebSocket decoded	—	20.4 KiB	—	29.3 KiB	✅
Codex	Live turn messages	—	2	—	8	✅
Claude	Total thread wire	—	4.9 KiB	—	6.8 KiB	✅
Claude	Thread snapshot wire	—	3.7 KiB	—	4.9 KiB	✅
Claude	Live turn WebSocket wire	—	1.2 KiB	—	2.0 KiB	✅
Claude	Live turn WebSocket decoded	—	20.7 KiB	—	29.3 KiB	✅
Claude	Live turn messages	—	1	—	8	✅

Baseline: unavailable · PR result: 16fd173 · Source CI: success

Scenario and decoded snapshot size

10 historical turns, 5 command tools per turn, 878.9 KiB retained MCP result per historical turn, and a 1.05 MiB retained result in the measured turn.

• Codex decoded thread snapshot: 106.1 KiB
• Claude decoded thread snapshot: 106.4 KiB

Updated in place by a trusted workflow. PR artifacts are strictly validated and never executed.

[macroscopeapp]

Approvability

Verdict: Approved at 16fd173

Macroscope's review found this PR approvable — This is a narrowly scoped replay-harness compatibility fix that defaults only legacy user-input frames to blocking while preserving explicit values. Its runtime impact is confined to test/evaluation replay paths, with no production, schema, security, or deployment changes.

^{You can add or adjust custom eligibility rules. Learn more.}