RivetKit action can hit closed SQLite coordinator immediately after local engine restart

Description

With RivetKit 2.3.10 and the bundled rivet-engine 2.3.10, an actor action invoked immediately after restarting the local engine/registry failed once with SQLite transaction coordinator is closed. Retrying the same action after a short delay succeeded. The engine log suggested this happened while the actor generation was syncing.

Environment

• RivetKit: 2.3.10
• rivet-engine: 2.3.10 from @rivetkit/engine-cli
• Runtime: Bun 1.3.14
• Platform: macOS arm64
• Actor database: embedded SQLite via rivetkit/db/drizzle

Reproduction sequence

1. Start a local registry with registry.start() and let RivetKit spawn/reuse the local engine.
2. Create an actor and call an action that reads its embedded SQLite database.
3. Stop the Bun registry process and restart the local engine/registry.
4. Immediately call the same actor action from a separate client process.
5. The first call can fail with SQLite transaction coordinator is closed; a short delayed retry succeeds.

I have only observed this once so far, so the timing window is transient rather than a deterministic reproduction.

Workaround

A client-side retry limited to this exact error, with short bounded backoff (100/250/500 ms), handles the observed failure.

Is this a known actor-generation synchronization race, and is there a readiness signal or more specific structured error code clients should use instead of matching the message?