The dashboard's FastAPI server and a terminal CLI are separate processes
sharing one SQLite session DB; there is no inter-process push channel.
The Sessions page polled the 50 newest sessions every 5s for the
"overview" card but only re-fetched the paginated sessions list on page
change or delete, so a session started in a terminal never appeared in
the list until the user navigated.
Reuse the existing 5s overview poll as a change signal: when the head
session id changes, silently reload the current page (no loading
spinner flicker, no scroll/reset of expanded rows or bulk selection,
which are keyed by id). The detection logic is extracted into a pure
shouldRefreshSessions() helper with unit tests. Adds a minimal vitest
setup for web/ (test script + config).
