Fix height of chat boxes

lib/screens/tasks/task_detail_screen.dart

@@ -2026,18 +2026,16 @@ class _TaskDetailScreenState extends ConsumerState<TaskDetailScreen>
             );
           }
 
-          // Mobile: make whole detail screen scrollable and give the
+          // Mobile: avoid two scrollables nested together. detailsCard can
-          // tabbed area a fixed height so it can layout inside the
+          // independently scroll and the tabbed card takes whatever space
-          // scrollable column.
+          // remains so the chat/activity list always receives gestures and
-          final mobileTabHeight = MediaQuery.of(context).size.height * 0.72;
+          // can never be pushed completely offscreen.
-          return SingleChildScrollView(
+          return Column(
-            child: Column(
             children: [
               detailsCard,
               const SizedBox(height: 12),
-                SizedBox(height: mobileTabHeight, child: tabbedCard),
+              Expanded(child: tabbedCard),
             ],
-            ),
           );
         },
       ),

lib/screens/tickets/ticket_detail_screen.dart

@@ -133,6 +133,13 @@ class _TicketDetailScreenState extends ConsumerState<TicketDetailScreen> {
                 ],
               ),
               const SizedBox(height: 12),
+              // collapse the rest of the details so tall chat areas won't push off-screen
+              ExpansionTile(
+                key: const Key('ticket-details-expansion'),
+                title: const Text('Details'),
+                initiallyExpanded: true,
+                childrenPadding: const EdgeInsets.only(top: 8),
+                children: [
                   Text(ticket.description),
                   const SizedBox(height: 12),
                   _buildTatRow(context, ticket, effectiveRespondedAt),
@@ -150,13 +157,16 @@ class _TicketDetailScreenState extends ConsumerState<TicketDetailScreen> {
                         const SizedBox(width: 8),
                         IconButton(
                           tooltip: 'Open task',
-                      onPressed: () => context.go('/tasks/${taskForTicket.id}'),
+                          onPressed: () =>
+                              context.go('/tasks/${taskForTicket.id}'),
                           icon: const Icon(Icons.open_in_new),
                         ),
                       ],
                     ),
                   ],
                 ],
+              ),
+            ],
           );
 
           final detailsCard = Card(
@@ -410,19 +420,16 @@ class _TicketDetailScreenState extends ConsumerState<TicketDetailScreen> {
             );
           }
 
-          // Mobile: make entire detail screen scrollable and give the
+          // Mobile: avoid nesting scrollables. detailsCard itself is
-          // messages area a fixed height so it can layout inside the
+          // scrollable if it grows tall, and the messages area takes the
-          // scrollable column.
+          // remaining space so the chat list can always receive touch
-          final mobileMessagesHeight =
+          // gestures and never end up offscreen.
-              MediaQuery.of(context).size.height * 0.72;
+          return Column(
-          return SingleChildScrollView(
-            child: Column(
             children: [
               detailsCard,
               const SizedBox(height: 12),
-                SizedBox(height: mobileMessagesHeight, child: messagesCard),
+              Expanded(child: messagesCard),
             ],
-            ),
           );
         },
       ),