Miler rider app: surface system, visible design language, backend lifecycle

Design system
- MilerSurface ladder (canvas → working → raised → floating) with MilerPanel
  as layer 1; canvas moved to #DEE3EA so white separates at 1.290:1.
- Visible vocabulary applied across Home, Deliveries, Activity, Account and
  the sheets: hero heads (tabular numeral + small caption, clamped at 1.3x),
  canvas wells for anything that opens, small filled tags for shelf labels,
  demoted placeholders. Recorded in DESIGN_SYSTEM.md §6.
- One icon family: 222 Material glyphs migrated to Lucide; none left outside
  lib/xpress.
- Colour semantics corrected: amber only for what is genuinely owed, brand red
  reserved for the live stop, disabled primaries go neutral rather than pale.

Data and lifecycle
- lib/data/lifecycle.dart reads mutations for what they prove; route_order.dart
  makes admin sequence the single ordering authority; service_day.dart, and
  stop_area.dart rewritten against live Coimbatore addresses (digit-token
  stripping, city stoplist, street suffixes, stammer collapse).
- countLabel states the load once, in bags.

Testing
- 1440 tests passing; golden shot harnesses for Home, Deliveries, Activity,
  sheets and verify, with test/failures/ now gitignored (diff debris).
- New pins: home_gutter_test, stop_area_test, plus updated structural bounds.

Note: this commit also carries pre-existing working-tree deletions that were
present before this work (API_SPEC.md, README.md, demo test fixtures).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

test/device_id_test.dart

@@ -0,0 +1,75 @@
+import 'package:flutter_test/flutter_test.dart';
+import 'package:shared_preferences/shared_preferences.dart';
+
+import 'package:miler/utils/device.dart';
+
+/// ─────────────────────────────────────────────────────────────────────────
+/// THE SIGN-IN MUST NOT DIE ON A FIELD IT DOES NOT SEND
+///
+/// `ensureDeviceId` threw on every unhappy path, and it is awaited on the line
+/// before the PIN check posts — inside the sign-in's outer `try`. So the throw
+/// was caught as "Could not reach the server" before a single byte left the
+/// phone, and the MPIN screen then reported it as **"Incorrect MPIN"**. For
+/// every phone number, on every attempt.
+///
+/// It threw for a guaranteed reason, not a rare one: it asked for
+/// `androidInfo` unconditionally, which raises on iOS.
+///
+/// There are no platform channels in a widget test, so `device_info_plus`
+/// raises `MissingPluginException` here — which makes this file an exact
+/// reproduction of the iOS path. Under the old code every test below throws.
+/// ─────────────────────────────────────────────────────────────────────────
+void main() {
+  TestWidgetsFlutterBinding.ensureInitialized();
+
+  setUp(() => SharedPreferences.setMockInitialValues({}));
+
+  test('hands back an id even when the platform cannot supply one', () async {
+    final prefs = await SharedPreferences.getInstance();
+
+    final id = await DeviceUtils.ensureDeviceId(prefs);
+
+    expect(id, isNotEmpty, reason: 'a sign-in cannot wait for a device id');
+    expect(
+      id,
+      startsWith(DeviceUtils.unknownDeviceId),
+      reason: 'a generated id says so, so a log can be read honestly',
+    );
+  });
+
+  test('the id is stable across calls — that is the whole job', () async {
+    final prefs = await SharedPreferences.getInstance();
+
+    final first = await DeviceUtils.ensureDeviceId(prefs);
+    final second = await DeviceUtils.ensureDeviceId(prefs);
+
+    expect(second, first);
+    expect(prefs.getString('deviceId'), first);
+  });
+
+  test('a stored hardware id is never replaced by a generated one', () async {
+    SharedPreferences.setMockInitialValues({'deviceId': 'real-hardware-id'});
+    final prefs = await SharedPreferences.getInstance();
+
+    expect(await DeviceUtils.ensureDeviceId(prefs), 'real-hardware-id');
+  });
+
+  test('two installs do not collide', () async {
+    final prefs = await SharedPreferences.getInstance();
+    final a = await DeviceUtils.ensureDeviceId(prefs);
+
+    SharedPreferences.setMockInitialValues({});
+    final b = await DeviceUtils.ensureDeviceId(
+      await SharedPreferences.getInstance(),
+    );
+
+    expect(a, isNot(b));
+  });
+
+  test('the push token degrades to empty rather than throwing', () async {
+    // Same contract, for the same reason: a rider who declined notifications
+    // still has a shift to start.
+    final prefs = await SharedPreferences.getInstance();
+    expect(await DeviceUtils.ensureFcmToken(prefs), '');
+  });
+}