FX.129 Teams page flashed an empty list for about 1.5 s before the members appeared

On a fresh load the Teams page drew its empty states until the account connected and the first sync brought the rows in. Now the page says 'Loading your teams (N teams, N people)' with a spinner while the first sync of the visit is pending. Where the count comes from, in order: (1) the account itself: app-shell.inc prints #cc-account-hints {teams:{teams,people}} for the signed-in person on /lab/supercadcraft (UserTeams::hint: two counts, never creates a database), so it works in a browser that has never synced; (2) otherwise a marker this browser kept at its last good sync. A hint of none wins over an older marker. It gives up after 15 s and tells the truth (empty, or the sync error); an account with no teams sees the empty state at once. Tests: teams 321, user-teams 118. Not done: the rows themselves are not cached locally; the hint is only printed for signed-in site sessions (a device-token-only window falls back to the browser marker); never opened in a real browser window.