action_sheet: Put mark-channel-as-read button at top of action sheet

As in the Figma:
  https://www.figma.com/design/1JTNtYo9memgW7vV6d0ygq/Zulip-Mobile?node-id=6812-34593&m=dev

Author: chrisbobbe

lib/widgets/action_sheet.dart

@@ -241,24 +241,25 @@ void showChannelActionSheet(BuildContext context, {
   final pageContext = PageRoot.contextOf(context);
   final store = PerAccountStoreWidget.of(pageContext);
 
-  final optionButtons = <ActionSheetMenuItemButton>[
-    TopicListButton(pageContext: pageContext, channelId: channelId),
-  ];
+  final optionButtons = <ActionSheetMenuItemButton>[];
 
   final unreadCount = store.unreads.countInChannelNarrow(channelId);
   if (unreadCount > 0) {
     optionButtons.add(
       MarkChannelAsReadButton(pageContext: pageContext, channelId: channelId));
   }
 
+  optionButtons.add(
+    TopicListButton(pageContext: pageContext, channelId: channelId));
+
   optionButtons.add(
     CopyChannelLinkButton(channelId: channelId, pageContext: pageContext));
 
   _showActionSheet(pageContext, optionButtons: optionButtons);
 }
 
-class TopicListButton extends ActionSheetMenuItemButton {
-  const TopicListButton({
+class MarkChannelAsReadButton extends ActionSheetMenuItemButton {
+  const MarkChannelAsReadButton({
     super.key,
     required this.channelId,
     required super.pageContext,
@@ -267,22 +268,22 @@ class TopicListButton extends ActionSheetMenuItemButton {
   final int channelId;
 
   @override
-  IconData get icon => ZulipIcons.topics;
+  IconData get icon => ZulipIcons.message_checked;
 
   @override
   String label(ZulipLocalizations zulipLocalizations) {
-    return zulipLocalizations.actionSheetOptionListOfTopics;
+    return zulipLocalizations.actionSheetOptionMarkChannelAsRead;
   }
 
   @override
-  void onPressed() {
-    Navigator.push(pageContext,
-      TopicListPage.buildRoute(context: pageContext, streamId: channelId));
+  void onPressed() async {
+    final narrow = ChannelNarrow(channelId);
+    await ZulipAction.markNarrowAsRead(pageContext, narrow);
   }
 }
 
-class MarkChannelAsReadButton extends ActionSheetMenuItemButton {
-  const MarkChannelAsReadButton({
+class TopicListButton extends ActionSheetMenuItemButton {
+  const TopicListButton({
     super.key,
     required this.channelId,
     required super.pageContext,
@@ -291,17 +292,17 @@ class MarkChannelAsReadButton extends ActionSheetMenuItemButton {
   final int channelId;
 
   @override
-  IconData get icon => ZulipIcons.message_checked;
+  IconData get icon => ZulipIcons.topics;
 
   @override
   String label(ZulipLocalizations zulipLocalizations) {
-    return zulipLocalizations.actionSheetOptionMarkChannelAsRead;
+    return zulipLocalizations.actionSheetOptionListOfTopics;
   }
 
   @override
-  void onPressed() async {
-    final narrow = ChannelNarrow(channelId);
-    await ZulipAction.markNarrowAsRead(pageContext, narrow);
+  void onPressed() {
+    Navigator.push(pageContext,
+      TopicListPage.buildRoute(context: pageContext, streamId: channelId));
   }
 }
 

test/widgets/action_sheet_test.dart

@@ -247,8 +247,8 @@ void main() {
     group('showChannelActionSheet', () {
       void checkButtons() {
         check(actionSheetFinder).findsOne();
-        checkButton('List of topics');
         checkButton('Mark channel as read');
+        checkButton('List of topics');
         checkButton('Copy link to channel');
       }
 
@@ -291,19 +291,6 @@ void main() {
       });
     });
 
-    testWidgets('TopicListButton', (tester) async {
-      await prepare();
-      await showFromAppBar(tester,
-        narrow: ChannelNarrow(someChannel.streamId));
-
-      connection.prepare(json: GetStreamTopicsResult(topics: [
-        eg.getStreamTopicsEntry(name: 'some topic foo'),
-      ]).toJson());
-      await tester.tap(findButtonForLabel('List of topics'));
-      await tester.pumpAndSettle();
-      check(find.text('some topic foo')).findsOne();
-    });
-
     group('MarkChannelAsReadButton', () {
       void checkRequest(int channelId) {
         check(connection.takeRequests()).single.isA<http.Request>()
@@ -350,6 +337,19 @@ void main() {
       });
     });
 
+    testWidgets('TopicListButton', (tester) async {
+      await prepare();
+      await showFromAppBar(tester,
+        narrow: ChannelNarrow(someChannel.streamId));
+
+      connection.prepare(json: GetStreamTopicsResult(topics: [
+        eg.getStreamTopicsEntry(name: 'some topic foo'),
+      ]).toJson());
+      await tester.tap(findButtonForLabel('List of topics'));
+      await tester.pumpAndSettle();
+      check(find.text('some topic foo')).findsOne();
+    });
+
     group('CopyChannelLinkButton', () {
       setUp(() async {
         TestDefaultBinaryMessengerBinding.instance.defaultBinaryMessenger.setMockMethodCallHandler(