Keysat
91af0b711e
iPad users hit a spurious "network error" on the first tap of "Send sign-in link", with a second tap succeeding. Cause is iOS Safari dispatching the POST onto a pooled keep-alive socket the server/proxy already closed; unlike a GET it isn't transparently re-sent, so it surfaces as a transport TypeError. The single 500ms auto-retry was too quick and reused the same dead socket. Both sign-in entry points (auth.html postWithRetry, index.html fetchWithRetry) now retry 3x with growing backoff (0 -> +400ms -> +1.6s) to outlast Safari evicting the socket. Frontend-only. Ships as 0.2.156.
