App structure: a swipe-in menu shell; pages/, link/, actions/; Settings

The shell (shell.dart): a drawer from the left edge or each page's menu button.
Dash, Signals, Captures; Tools (Camera, Link test, Orin power options), the
rarely used ones, after pirate-station-aide; Settings (gateway address, dark/bright,
build-time theme and landing). Landing view at build time: YUKART_HOME=dash|signals,
signals for now. Dash, Signals and Captures stay alive while hidden; Captures has its
own navigator, so a run survives switching views. Back goes inside Captures, then to
the landing view, then out. The mock banner sits over every page.

main.dart is startup only; the old home screen is pages/signals.dart; dialogs and
sheets moved to actions/; the protocol client, USB binding and Reading to link/.
lib/README.md catalogues it.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01DDwfd6Ki8UfG4hK6W5YpJz

lib/widgets/link_status.dart

@@ -0,0 +1,71 @@
+// The link to the Orin at a glance: the state chip, and the details behind it.
+
+import 'package:flutter/material.dart';
+
+import '../link/boundary.dart';
+import '../link/net.dart';
+import '../theme/palette.dart';
+
+/// CONNECTED / CONNECTING / DOWN in good / caution / alarm.
+class LinkChip extends StatelessWidget {
+  const LinkChip({super.key, required this.boundary});
+  final Boundary boundary;
+
+  @override
+  Widget build(BuildContext context) {
+    final p = AppTheme.of(context);
+    final (color, label) = switch (boundary.state) {
+      LinkState.up => (p.good, 'CONNECTED'),
+      LinkState.connecting => (p.caution, 'CONNECTING'),
+      LinkState.down => (p.alarm, 'DOWN'),
+    };
+    return Chip(
+      label: Text(
+        label,
+        style: TextStyle(color: color, fontWeight: FontWeight.w600),
+      ),
+      backgroundColor: color.withValues(alpha: 0.3),
+      side: BorderSide.none,
+      visualDensity: VisualDensity.compact,
+    );
+  }
+}
+
+/// Address, gateway, last-message age, clock offset, USB link. Fixed-width numbers,
+/// padded with figure spaces (U+2007, digit-wide): nothing reflows as a value gains a digit.
+class LinkDetails extends StatelessWidget {
+  const LinkDetails({super.key, required this.boundary, required this.usb});
+  final Boundary boundary;
+  final UsbLink usb;
+
+  @override
+  Widget build(BuildContext context) {
+    final b = boundary;
+    String pad(String v, int n) => v.padLeft(n, ' ');
+    final age = b.lastMessage == null
+        ? pad('—', 4)
+        : pad(
+            '${DateTime.now().difference(b.lastMessage!).inMilliseconds.clamp(0, 9999)}',
+            4,
+          );
+    final offset = b.clockOffset == null
+        ? pad('—', 6)
+        : pad((b.clockOffset!.inMilliseconds / 1000).toStringAsFixed(1), 6);
+    const fixed = TextStyle(fontFeatures: [FontFeature.tabularFigures()]);
+    return Wrap(
+      spacing: 16,
+      runSpacing: 4,
+      crossAxisAlignment: WrapCrossAlignment.center,
+      children: [
+        Text(b.url, style: const TextStyle(fontFamily: 'monospace')),
+        Text(b.detail),
+        Text('last msg $age ms', style: fixed),
+        Text('Orin−tablet clock $offset s', style: fixed),
+        if (usb.supported)
+          Text(
+            'USB link ${usb.up ? 'up' : 'absent'}${usb.bound ? ', bound' : ''}',
+          ),
+      ],
+    );
+  }
+}

lib/widgets/mock_banner.dart

@@ -0,0 +1,28 @@
+// Mock data must look like mock data: on the surface of every page, not in a menu.
+
+import 'package:flutter/material.dart';
+
+import '../theme/palette.dart';
+
+class MockBanner extends StatelessWidget {
+  const MockBanner({super.key});
+
+  @override
+  Widget build(BuildContext context) {
+    final p = AppTheme.of(context);
+    return Container(
+      color: p.caution,
+      padding: const EdgeInsets.symmetric(vertical: 6),
+      child: Text(
+        'MOCK DATA — NOT FROM THE CAR',
+        textAlign: TextAlign.center,
+        style: TextStyle(
+          color: p.onFill(p.caution),
+          fontWeight: FontWeight.w900,
+          fontSize: 20,
+          letterSpacing: 2,
+        ),
+      ),
+    );
+  }
+}

lib/widgets/telltale.dart

@@ -1,9 +1,9 @@
 // An on/off lamp in the boxed pattern (lib/widgets/stat_box.dart): the label is the
-// lamp. Takes a [Reading] (lib/reading.dart) so missing and stale draw as they do elsewhere.
+// lamp. Takes a [Reading] (lib/link/reading.dart) so missing and stale draw as they do elsewhere.
 
 import 'package:flutter/material.dart';
 
-import '../reading.dart';
+import '../link/reading.dart';
 import '../theme/palette.dart';
 
 /// An on/off lamp in the boxed pattern: the label is the lamp. Lit in foreground