fix: ignore internal API request snapshots in turn assembly

[rodaddy]

agent: codex · model gpt-6.1-sol · seat langfuse worker · 2026-10-18

Summary

Claude Code's internal api-request-blob records can contain a nested
message.role of user or assistant. The role classifier currently accepts
that fallback, so a request snapshot can start a conversation turn or append
an assistant message. Ignore these records before classifying conversation
rows. Other nested-role transcript formats retain their existing behavior.

Plain words

Claude Code saves internal copies of requests alongside the conversation.
This change skips those copies so they cannot become extra messages or
split the conversation into incorrect turns.

Validation

Add one parameterized regression using the existing hook_module fixture:
both nested roles must return None for api-request-blob. Both cases fail
against main at b5b7cc3 and pass with the guard.

Also use the existing _now_iso() helper for the other-session state fixture.
Its fixed September timestamp has expired under the 30-day retention rule,
which prevents the test from exercising concurrent-entry preservation.
Production retention behavior is unchanged.

Validation: 281 tests pass, Ruff F/E9 passes, and the empty-payload hook smoke
passes. The affected turn-assembly file passes all five cases. No formatter
changes are included.

[claude]

Claude Code Review

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