Adds a real Ch∆In hub backend to the Flutter client as a
sibling-path dependency on chain_client_sdk_dart, alongside the
existing MockRepository (which stays the default until the
flow.completed-to-Evaluation pipeline lands in Phase 0 week 1).
Wiring
HubSettings (lib/data/hub_endpoint.dart) — persists host /
port / secure / token / useHub flags via SharedPreferences
under the Studio-compatible hub.* keys. Distinct from the
SDK's chain.HubEndpoint, which is a transport-level value
type — HubSettings adapts in that direction.
HubRepository (lib/data/hub_repository.dart) — implements
EvaluationRepository on top of HubClient. connect() runs a
4-second healthy() probe; on failure returns a repository
with isHealthy=false rather than throwing, so the UI can
surface "hub-down" without an exception-handling round-trip.
list() / byEli() return empty data in Phase 0 because no
hub-side flow yet produces Evaluation objects in the
lawheatmap-specific shape.
main.dart — loads HubSettings on startup; if useHub=false
starts with MockRepository (fast offline default), otherwise
probes the hub and falls back to MockRepository on probe
failure. No mid-session swap to keep the Phase 0 wiring
simple; a settings save instructs the user to restart.
HubStatusPage — read-only summary card at the top, editable
endpoint form, "Verbindung testen" probe button, "Speichern"
persist button. Live-flow runbook below describes the
chain serve / install / run / approve sequence so a user
can wire the real flow themselves once Phase 1 lands.
flutter analyze: clean. flutter test: 2/2 passing.
Smoke-launch on macOS: app boots, Dart VM service comes up,
no runtime errors in mock mode.
Signed-off-by: flemming-it <sf@flemming.it>
