feat(session-persistence): preserve interrupted turns on crash; don't truncate (review #33)

A crash can leave a durable log whose final turn never closed. The old behavior truncated everything after the last turn/end as a "crash tail". But a single turn can be HUGE in a long-horizon task (many steps, large tool output), so truncating it silently destroys real, durably-written work — truncating a turn is wrong. New crash recovery (ADR 0018): load() PRESERVES the interrupted turn's events and CLOSES the orphaned turn by durably appending synthetic boundary events — a step/end if a step was open, then a turn/end carrying the new merge-extensible TurnEndReason {kind:'interrupted'}. load() returns the balanced log, so a resumed session is immediately usable. Only a never-fully-written TORN tail fragment is discarded; corruption in the committed region is still unloadable. - dsh-session: TurnEndReason {kind:'interrupted'} + shared interruptedTurnClosers() repair helper. - JSONL backend: scanLog preserves the longest contiguous prefix (including a partial final turn); loadCore truncates a torn fragment and durably writes the closers, returning the balanced log. - runPersistenceContract gains a crash-recovery test (both backends + mock). - Docs: ADR 0018/0017, architecture.md, package READMEs. Also (review #33): RFC 013 records the "move event vocabulary to Zod" question (merge-extensible maps → runtime schema registry) + blast radius; deferred, not done here.
2026-06-16 21:27:50 +08:00
parent 96331432b8
commit efee449cfe
16 changed files with 361 additions and 104 deletions
@@ -16,3 +16,4 @@ Proposals for substantial future work — reviewed before implementation, unlike
 | [010](010-acp-agent-client-protocol.md) | Agent Client Protocol (ACP) support for external editors | proposed |
 | [011](011-acp-multi-session.md) | Multiplex concurrent ACP sessions over one connection | proposed |
 | [012](012-optional-code-mode.md) | Optional Code Mode — model writes TypeScript against an SDK of all tools | proposed |
+| [013](013-typed-event-schemas.md) | Runtime schemas for the event vocabulary (Zod vs the merge-extensible-map pattern) | proposed |