Approve-with-comments re-review; no blockers. All 7 actionable points (8 is a
forward-looking architecture note — recommendation A, keep as-is):
1. chat-markdown.util spec: restore parity coverage of the removed client spec —
tool error state (+ errorText), unknown-tool fallback (`Ran tool <name>` en /
`Выполнил инструмент <name>` ru), and the circular-output stringify catch.
2. findAllByChat row cap is now testable (injectable limit) + an int-spec proves
truncation on a modest volume.
3. Stability: the per-step durability updates are SERIALIZED via a promise chain
(stepUpdateChain) so they commit in step order — onlyIfStreaming already
closed the finalize race, this closes inter-step ordering.
4. findAllByChat keeps the NEWEST messages on truncation (order DESC + reverse,
like findRecent) and logs a warning with chatId, instead of silently dropping
the newest tail.
5. The LABELS parity comment already references the real path (tool-parts.tsx /
toolLabelKey) — confirmed accurate.
6. Removed the redundant 'off-by-one boundary' test (strict subset of the two
adjacent prepareAgentStep cases).
7. Extracted the terminal-finalize dispatch into a shared `applyFinalize`, used
by BOTH the service's finalizeAssistant and its test — the test now exercises
the real path, not a copy, so a production drift fails it.
Verified: server build + 325 ai-chat unit + 6 integration; prettier clean.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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