Brings the latest dev (45 commits) into v2. Conflict resolutions:
- core/src/session.ts: keep v2's Service (BusyError active-checks in
revert.stage/clear/commit, rename method + Renamed event) and add
dev's history method. v2's Renamed event flows through the merged
SessionEvent.Definitions into the OpenCodeEvent union, so it encodes
correctly on the SSE stream.
- server/src/handlers/event.ts: take dev's OpenCodeEvent encoder, which
supersedes v2's PublicEventManifest handler wiring. This also brings
dev's live event stream (allBounded + heartbeat + keepalive headers)
onto v2.
- Removed the now-orphaned public-event-manifest.ts (only self-referenced
after taking dev's handler).
- Generated client + sdk types regenerated via codegen (not hand-merged);
they pick up dev's effect SSE OpenAPI-naming patch (V2EventStream).
