connection binds the web transport: it injects httpServer + apiProxy and
registers toFetchHandler(ctx.apiProxy) under the /api prefix (the node:http
to fetch bridge moves in from the webserver, keeping the res-close disconnect
detection and drain/close backpressure waits). hmr owns dev reload: a
stat-poll watch per graph row driven by clientModuleHost.onGraphChanged,
rebuilt(id) on content change, and the /plugins/events SSE route (GET/HEAD
guarded); frame types are single-sourced in events.ts shared by both halves.
imccyu