ApiClient.buildDio takes on401; the library's dioProvider wires it to
the auth controller's clearSession. The router redirect already handles
navigation away from authed screens once the session goes null.
HomeScreen surfaces the banner on connection_refused with Retry +
Change URL.
ApiError.fromDio handles both server envelope shapes: {"error":"code"}
(admin endpoints) and {"error":{"code","message"}} (most others). Same
dual-shape problem the web apiFetch already solves. Token comes from a
resolver function so the auth provider can swap implementations
without touching the client.
ErrorCopy is a lazy singleton over assets/error-copy.json with the
same fallback chain web uses (specific code -> unknown -> hard-coded).
bvandeusen