Eight files under src/live/:
- constants.ts: throughput-discipline numbers (MAX_TRAIL_LENGTH=200,
reconnect backoff [1s/2s/4s/8s/16s, 30s ceiling], STALE_CONNECTION_MS).
- protocol.ts: zod discriminatedUnion('type', ...) for inbound
(subscribed / unsubscribed / position / error). PositionEntry +
SubscribeResult types per processor-ws-contract.
- connection-store.ts: Zustand store with status state machine.
- position-store.ts: Zustand store with latestByDevice + trailsByDevice
Maps, applySnapshot/applyPositions/clearForEvent/selectDevice
actions. Ring-buffer cap on trails; same-coordinate dedup.
- coalescer.ts: ~30-line rAF coalescer. Per-device buffer; flushes once
per animation frame regardless of receive rate.
- ws-client.ts: state machine (idle / connecting / connected /
reconnecting / closed) with exponential backoff, re-subscribe on
reconnect, stale-connection check, subscribe correlation via
pending-map + 5s timeout. URL resolution helper toAbsoluteWsUrl()
for same-origin path inputs.
- bootstrap.tsx: <LiveBootstrap> creates the client when authenticated,
wires positions through the coalescer to the position store, tears
down on logout. getLiveClient() exposes the singleton for 2.7.
- index.ts: barrel re-exports.
main.tsx wraps <App /> in <LiveBootstrap> alongside <AuthBootstrap>.
Deviations:
1. Skipped the setStatus helper inside createLiveClient; conditional
Parameters<> generics were hostile. Direct
useConnectionStore.getState().setStatus(...) at the ~6 call sites.
2. subscribe() adds to the subscriptions Set even when not connected
(so it replays on reconnect). Caller handles 'not-connected' by
waiting for connection-store status transition.
3. onPosition returns an unsubscribe fn (Set-based). Multi-handler is
free; lets future debug panels/tests attach.
Bundle: src/live/ adds ~15KB raw to the main bundle (mostly zod's
discriminated-union runtime). Total 393KB / 120KB gz.
