Verified: provider tests (fake remote: names/kinds, buttons stripped, third-magpie cards dropped, one ask per 30s, refresh paths, unreachable keeps last cards, 404 → update card, cache-only CachedCards, histories) and the gateway test (an in-process gateway with a fake balance vendor counting hits, asked through a remote-magpie provider: nothing read until a refresh, 5 card asks read nothing, two refreshes of a card read once, a remote card's refresh 400, another machine without the key refused) pass with -race -count=20; go test provider/gateway/gui/tui/root, vet, linux and windows builds pass. Two sandbox gateways (3481 with a fake balance vendor, 3482 with it as remote-magpie): magpie quota on the second showed the "nothing read" card with 0 vendor hits, then office/bal "Bal · Office" $12.00 after one refresh (1 hit), 10 more asks 0 hits, two card refreshes 1 hit. usage-remote-cards (names, translated remote errors, refresh ids) passes in Chromium and WebKit, en/zh/ja/de and fails without the app.js change; i18n-keys, gui-ja, gui-de, usage-card-refresh, usage-refresh, quota-reading-again pass. Not tried with a real second computer.