[Chat] Fix navigation stacking on messages links in split view (#10741)

Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/screens/Messages/ChatList.tsx

@@ -451,6 +451,12 @@ export function Header({
   const {gtMobile} = useBreakpoints()
   const requireEmailVerification = useRequireEmailVerification()
   const leftConvos = useLeftConvos()
+  const {isWithinSplitView} = useIsWithinSplitView()
+
+  // In split view, the left column (and this header) stays mounted while the
+  // right column shows the selected route. Pushing would stack duplicate routes
+  // on repeated clicks, so navigate instead to dedupe by route + params.
+  const action = isWithinSplitView ? 'navigate' : 'push'
 
   const {data: unreadInboxData, hasNextPage: hasMoreRequests} =
     useListConvosQuery({
@@ -494,9 +500,11 @@ export function Header({
               count={inboxAllConvos.length}
               more={hasMoreRequests}
               variant="solid"
+              action={action}
             />
             <Link
               to="/messages/settings"
+              action={action}
               label={l`Chat settings`}
               size="small"
               color="secondary"

src/screens/Messages/components/ChatListItem.tsx

@@ -481,6 +481,9 @@ function BaseChatItem({
 
           <Link
             to={`/messages/${convo.view.id}`}
+            // In split view, this list stays mounted alongside the open convo,
+            // so push would stack duplicate routes on repeated clicks.
+            action={isWithinSplitView ? 'navigate' : 'push'}
             label={title}
             accessibilityHint={accessibilityHint}
             accessibilityActions={

src/screens/Messages/components/InboxRequests.tsx

@@ -11,10 +11,12 @@ export function InboxRequests({
   count,
   more,
   variant,
+  action,
 }: {
   count: number
   more: boolean
   variant?: 'ghost' | 'solid'
+  action?: 'push' | 'navigate'
 }) {
   const {t: l} = useLingui()
 
@@ -41,6 +43,7 @@ export function InboxRequests({
         <Link
           label={label}
           to="/messages/inbox"
+          action={action}
           size="small"
           variant={unread ? 'solid' : 'ghost'}
           color={unread ? 'primary_subtle' : 'secondary'}
@@ -66,6 +69,7 @@ export function InboxRequests({
         <Link
           label={label}
           to="/messages/inbox"
+          action={action}
           color={unread ? 'primary_subtle' : 'secondary'}
           size="small">
           <ButtonIcon icon={InboxIcon} />