Session client — live demo

A working proof-of-concept of the session-mode client: makeServiceWorkerDb() — one shared, observable calculation surface across every open tab, built from a SharedWorker engine (the one pglite) plus a ServiceWorker controller (versioned control + notification singleton). See the design writeup in Service worker & the one-shot / session split.

Try it: run a query, then hit open 2nd tab — one engine serves both, and every query from either tab lands in the single cross-tab activity log. notify fans a toast to all tabs; flush SW replaces the controller and reloads.