docs: RELEASES.md entry for 8.2.2 (transaction timeout rollback)

RELEASES.md

@@ -10,6 +10,32 @@ Full auto-generated changelog: `CHANGELOG.md` · Releases: https://github.com/so
 
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+## v8.2.2 — 2026-07-11 (P0: a timed-out transaction now rolls back — no torn state)
+
+Data-integrity fix. A transaction that exceeded its time budget **mid-flight** (e.g. a bulk
+`transact()` on slower hardware crossing the 30s ceiling) threw a timeout error WITHOUT rolling
+back the operations it had already applied. The budget check sat outside the per-operation
+rollback path, so only per-operation *failures* rolled back — a timeout stranded the partial
+writes in canonical storage while the generation was never stamped, leaving torn, generation-less
+state. This was caught by a downstream migration that crossed the ceiling on a large batch.
+
+`Transaction.execute()` now has a **single rollback point**: any error that escapes the operation
+loop — an operation failure OR a mid-flight timeout — rolls back every applied operation in
+reverse order, then surfaces the original error (a rollback failure supersedes it, loudly, as
+before). This restores the invariant the generation-store commit path already depended on: a throw
+from execute means the applied operations were undone byte-identically, and the aborted
+transaction leaves `generation()` unchanged and storage byte-identical to its pre-transaction
+state.
+
+No API change. Regression pins the reported requirement — after a mid-flight timeout,
+storage is byte-identical and the transaction ends in the `rolled_back` terminal state
+(`tests/unit/transaction/timeout-rollback.test.ts`), plus the operation-failure and
+rollback-failure paths through the same single rollback point.
+
+**Note on the 30s ceiling itself** (configurable/scaled timeout, batched embedding precompute,
+timeout telemetry) — that ergonomics work is tracked separately; this release fixes only the
+correctness bug (a timeout must never leave partial state), independent of where the ceiling sits.
+
 ## v8.2.1 — 2026-07-11 (transact forward references work on the native accelerator)
 
 Parity fix. `transact()` has always promised atomic forward references — `add` an entity and