feat(train): a recording under way above the bar on every tab, and a saved one opens its page (ADR 0030, D60)

halkyon_ui's NavigationFrame takes a status, standing above the floating
bar below medium windows and at the foot of the screen's panel from there
on. Train's RecordingBar fills it while a recording runs or waits to be
saved: its activity, moving time and distance, paused or stopped, a tap
back to it. Saving now opens the workout's page in Home's tab.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Signed-off-by: Tizian 「ティツィアーン」 <raisondetredev@pm.me>

packages/halkyon_ui/README.md

@@ -29,7 +29,8 @@ LeanCode's lints.
   `TopGradient`, `ScreenTint`, `ScreenColor`, `TintFrame`, `FramedScreen`
   and `TabVisibility`; `FloatingNavigationBar`, and `NavigationFrame`, every
   app's frame around its tabs (the rail with the app's icon, the floating
-  bar, a tick on every choice), whichever router drives it;
+  bar, a tick on every choice, a status such as a recording under way above
+  the bar), whichever router drives it;
   `AppLoadingIndicator`, `ButtonLoadingIndicator`, `AppRefreshIndicator`;
   `SectionCard`, `SliverCentered`, `EmptyListMessage`, `CountBadge`,
   `TitleWithKicker`, `CollapsingRow`, `ScrollHidingFab`, `liftWhileDragged`,

packages/halkyon_ui/lib/src/widget/navigation_frame.dart

@@ -54,6 +54,12 @@ class const NavigationFrame({
   /// top-level screens and the actions of those below in a toolbar, never
   /// both at once (as Vaia does). The rail of wider windows stays.
   final bool hidesNavigationBar = false,
+
+  /// What stands above the bar on every tab while it matters (Train's
+  /// recording under way, as Strava's): floating above the bar below
+  /// medium windows, at the foot of the screen's panel from there on; none
+  /// while null.
+  final Widget? status,
   super.key,
 }) extends StatefulWidget {
   @override
@@ -102,7 +108,15 @@ class _NavigationFrameState() extends State<NavigationFrame> {
                 ),
             ],
           ),
-          child: widget.child,
+          child: switch (widget.status) {
+            final status? => Column(
+              children: [
+                Expanded(child: widget.child),
+                Padding(padding: const EdgeInsets.all(12), child: status),
+              ],
+            ),
+            null => widget.child,
+          },
         ),
       );
     }
@@ -142,9 +156,30 @@ class _NavigationFrameState() extends State<NavigationFrame> {
             // Without the bar, a strip as high as the system's own bar, in
             // the screen's background, keeps every screen inside clear of
             // it.
-            bottomNavigationBar: widget.hidesNavigationBar
-                ? SizedBox(height: MediaQuery.paddingOf(context).bottom)
-                : bar,
+            bottomNavigationBar: switch (widget.status) {
+              final status? => Column(
+                mainAxisSize: MainAxisSize.min,
+                children: [
+                  Padding(
+                    padding: const EdgeInsets.fromLTRB(
+                      FloatingNavigationBar.sideMargin,
+                      0,
+                      FloatingNavigationBar.sideMargin,
+                      FloatingNavigationBar.lift,
+                    ),
+                    child: status,
+                  ),
+                  if (widget.hidesNavigationBar)
+                    SizedBox(height: MediaQuery.paddingOf(context).bottom)
+                  else
+                    bar,
+                ],
+              ),
+              null when widget.hidesNavigationBar => SizedBox(
+                height: MediaQuery.paddingOf(context).bottom,
+              ),
+              null => bar,
+            },
           ),
         ),
       ),

packages/halkyon_ui/test/widget/navigation_frame_test.dart

@@ -160,4 +160,40 @@ void main() {
     expect(find.byType(FloatingNavigationBar), findsNothing);
     expect(tester.getBottomLeft(find.byType(Scaffold).last).dy, 800 - 24);
   });
+
+  testWidgets('a status stands above the bar below medium windows, and at '
+      "the foot of the screen's panel from there on", (tester) async {
+    for (final width in const [400.0, 800.0]) {
+      tester.view.physicalSize = Size(width, 800);
+      tester.view.devicePixelRatio = 1;
+      addTearDown(tester.view.reset);
+      await tester.pumpWidget(
+        testApp(
+          NavigationFrame(
+            appName: 'Halkyon Test',
+            icon: icon,
+            selectedIndex: 0,
+            onSelected: (_) {},
+            status: const Text('Recording'),
+            destinations: const [
+              (label: 'Home', icon: Icon(Icons.home), selectedIcon: null),
+              (label: 'Maps', icon: Icon(Icons.map), selectedIcon: null),
+            ],
+            child: const Scaffold(body: Text('The tab')),
+          ),
+        ),
+      );
+      await tester.pumpAndSettle();
+
+      final status = tester.getBottomLeft(find.text('Recording')).dy;
+      final tab = tester.getTopLeft(find.text('The tab')).dy;
+      expect(status, greaterThan(tab), reason: '$width');
+      if (width < 600) {
+        expect(
+          status,
+          lessThan(tester.getTopLeft(find.byType(NavigationBar)).dy),
+        );
+      }
+    }
+  });
 }