[SaladDay]

Summary

• Journaled Turn snapshots stripped the whole outcome, so agent.session.turn.failed events always reported internal_error while Turn reads reported the classified official code. Snapshots now keep only Core's error_code and the normalized model category; native codes, text, HTTP status and the Runtime result stay out of the journal.
• runtime_unavailable also covers Core failing to dispatch a Turn (execution_unavailable), so it now reports internal_error. Only a Runtime that disconnected or failed its preparation reports sandbox_error.
• Docs that still described the generic Turn error or the "never repeat caller input" rule (now broken by the official unknown-tool-call message) are corrected, with zh.

Checks

• go test sessions and api; go vet on both.
• DB: TestNativeClassificationPostgresRoundTripAndPublicPrivacy (now also asserts the streamed failed Turn carries the same public code).
• node --test website/tests/translations.test.mjs: hash tests pass; the inline-literals test needs vitepress, which is not installed locally.

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