fix(session): load pre-react-loop persisted sessions

packages/session-persistence/session-persistence/README.md

@@ -13,9 +13,9 @@ The persisted unit IS the existing `SessionEvent` (event-sourced model — the l
 | `locate(meta): SessionLocation \| undefined` | Resolve an absolute per-session artifact target without I/O or materialization. Backends without an independent local artifact return `undefined`. |
 | `create(meta): Promise<void>` | Register a new session's metadata. MAY defer the physical write until the first `append` (lazy materialization). |
 | `append(id, events): Promise<void>` | Durably persist a batch. Append-only; first event `seq` == stored next-seq after any repair; rejects non-JSON-serializable data naming the offending type. |
-| `load(id): Promise<{ meta; events }>` | Return a stored header plus a balanced contiguous log whose events are detached and validated and whose identified messages are deeply frozen. The coordinator upgrades the four pre-identity message event shapes into current wrappers in the returned snapshot; all other obsolete or malformed shapes still reject. A live load first flushes its snapshot and rejects while its turn is open; a cold load preserves an interrupted final turn and closes it with synthetic `tool/result`/`step/end?`/`turn/end {interrupted}` events. Only a torn tail fragment is dropped; committed corruption and unknown `version` reject. |
+| `load(id): Promise<{ meta; events }>` | Return a stored header plus a balanced contiguous log whose events are detached and validated and whose identified messages are deeply frozen. The coordinator upgrades the supported same-version message and pre-react-loop event shapes into the current read snapshot; all other obsolete or malformed shapes still reject. A live load first flushes its snapshot and rejects while its turn is open; a cold load preserves an interrupted final turn and closes it with synthetic `tool/result`/`step/end?`/`turn/end {interrupted}` events. Only a torn tail fragment is dropped; committed corruption and unknown `version` reject. |
 | `inspect(id, signal?): Promise<{ meta; events }>` | Return a detached valid stored prefix with upgraded, validated, deeply frozen identified messages, without truncating a torn tail, synthesizing recovery closers, or publishing coordinator state. Serialized with same-id writes; the optional signal promptly rejects a queued caller, prevents that queued backend read from starting, and cancels active backend read work. Intended for read models and other observers that must never recover a log. |
-| `readFrom(id, fromSeq, signal?): Promise<{ meta; events }>` | The read-from-seq primitive: return the header plus the valid stored events with `seq >= fromSeq`, detached and non-mutating like `inspect` (no truncation, no closers, no coordinator state). A `fromSeq` at or past the stored end returns an empty event list; a negative or non-safe-integer `fromSeq` rejects. Seek-capable backends (SQLite) read only the suffix; sequential backends (JSONL) still parse the whole artifact and skip forward — the primitive bounds what is returned and refolded, not every backend's physical read. Intended for checkpoint consumers (e.g. the persisted projection cache) that fold only the tail past a watermark. |
+| `readFrom(id, fromSeq, signal?): Promise<{ meta; events }>` | The read-from-seq primitive: return the header plus the valid stored events with `seq >= fromSeq`, detached and non-mutating like `inspect` (no truncation, no closers, no coordinator state). A `fromSeq` at or past the stored end returns an empty event list; a negative or non-safe-integer `fromSeq` rejects. Seek-capable backends (SQLite) read only the suffix unless a legacy event in that suffix requires prefix context for normalization; sequential backends (JSONL) parse the whole artifact and skip forward. Intended for checkpoint consumers (e.g. the persisted projection cache) that fold only the tail past a watermark. |
 | `list(signal?): Promise<SessionHeader[]>` | Lightweight listing from metadata, no full-log parse. The optional signal cancels backend listing work. A zero-event lazily-materialized session is absent from `list`. |
 | `listSnapshots(signal?): Promise<SessionPersistenceSnapshot[]>` | Lightweight metadata plus an opaque branded per-log revision, without loading event logs. A revision stays equal while that log and its backing store are unchanged, changes after append or mutating load repair, and cannot collide solely because two stores use the same local counter. The optional signal requests cancellation of backend discovery work; first-party backends settle any started listing work before rejecting so an awaited call is quiescent. |
 
@@ -34,7 +34,7 @@ Each `session/event` copies its event into the session controller and starts an
 
 Crash repair is cold-only. For a live id, `load(id)` snapshots the authoritative in-memory log, waits for that snapshot to become durable, and returns it with the coordinator's stored header only when balanced; an open live turn rejects instead of receiving synthetic interruption closers. A cold load reserves its id across backend reads and repair writes, so concurrent publication of a same-id live `Session` rejects and rolls back. HMR adoption reads through `loadStored`, applies the coordinator's cwd check, and never closes the active turn.
 
-Backend reads normalize pre-identity `user/message`, `assistant/message`, and `tool/result` payloads before current-shape validation. Each imported message receives the deterministic id `legacy-message:<session-id>:<event-seq>`; a tool-result content replacement inherits its target's imported id. The coordinator uses the same normalized view for `load`, `inspect`, ownerless-state claims, and HMR prefix adoption, so resumed sessions can append current events without a false prefix collision. Storage remains append-only: the read does not rewrite old records, and every later append uses the current shape. This is the narrow import exception from the [pre-identity message recovery decision](../../../.agents/notes/implemented/bug-fix/2026-07-28-load-pre-identity-session-messages.md), not a general v0 migration promise.
+Backend reads normalize the exact supported same-version shapes before current-shape validation. Pre-identity messages receive the deterministic id `legacy-message:<session-id>:<event-seq>`; a tool-result content replacement inherits its target's imported id. A pre-react-loop `turn/start` loses its obsolete trigger, a removed `steering/message` becomes the same identified `user/message`, and an older `turn/end` gains its last entered step while its terminal reason maps without inventing unavailable cancellation provenance. The coordinator uses the same normalized view for `load`, `inspect`, `readFrom`, ownerless-state claims, and HMR prefix adoption. Storage remains append-only: reads do not rewrite old records, and later appends use the current shape. These are narrow import exceptions from the [pre-identity message](../../../.agents/notes/implemented/bug-fix/2026-07-28-load-pre-identity-session-messages.md) and [pre-react-loop session](../../../.agents/notes/implemented/bug-fix/2026-08-04-load-pre-react-loop-sessions.md) decisions, not a general v0 migration promise.
 
 When a live session emits `session/disposed`, the coordinator waits for its controller, serializes a final drain, then releases state owned by that exact `Session` object. Failed retirement leaves the controller in the live-session map, so backend teardown can retry it. Backend teardown stops event admission first, flushes every remaining controller, awaits per-id operations, and only then closes the storage handle.