Handle account switch in RootFlowNode instead of in presenters

PreferencesRootPresenter and HomePresenter were updating the latest session
in the session store directly, relying on RootNavStateFlow to trigger the
navigation as a side effect. Changing the current session is app-level
navigation, so it is now forwarded through a new `navigateToSession` callback
up to RootFlowNode, which performs the session store update.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

features/home/api/src/main/kotlin/io/element/android/features/home/api/HomeEntryPoint.kt

@@ -14,6 +14,7 @@ import com.bumble.appyx.core.plugin.Plugin
 import io.element.android.libraries.architecture.FeatureEntryPoint
 import io.element.android.libraries.matrix.api.core.EventId
 import io.element.android.libraries.matrix.api.core.RoomId
+import io.element.android.libraries.matrix.api.core.SessionId
 import io.element.android.libraries.matrix.api.room.JoinedRoom
 
 interface HomeEntryPoint : FeatureEntryPoint {
@@ -33,5 +34,6 @@ interface HomeEntryPoint : FeatureEntryPoint {
         fun navigateToRoomSettings(roomId: RoomId)
         fun navigateToBugReport()
         fun navigateToAddAccount()
+        fun navigateToSession(sessionId: SessionId)
     }
 }

features/home/impl/src/main/kotlin/io/element/android/features/home/impl/HomeEvent.kt

@@ -8,10 +8,7 @@
 
 package io.element.android.features.home.impl
 
-import io.element.android.libraries.matrix.api.core.SessionId
-
 sealed interface HomeEvent {
     data class SelectHomeNavigationBarItem(val item: HomeNavigationBarItem) : HomeEvent
-    data class SwitchToAccount(val sessionId: SessionId) : HomeEvent
     data object DismissMultiAccountAnnouncement : HomeEvent
 }

features/home/impl/src/main/kotlin/io/element/android/features/home/impl/HomeFlowNode.kt

@@ -222,6 +222,7 @@ class HomeFlowNode(
                 onRoomClick = ::navigateToRoom,
                 onSettingsClick = callback::navigateToSettings,
                 onAddAccountClick = callback::navigateToAddAccount,
+                onSwitchToAccount = callback::navigateToSession,
                 onStartChatClick = callback::navigateToCreateRoom,
                 onCreateSpaceClick = callback::navigateToCreateSpace,
                 onSetUpRecoveryClick = callback::navigateToSetUpRecovery,

features/home/impl/src/main/kotlin/io/element/android/features/home/impl/HomePresenter.kt

@@ -126,9 +126,6 @@ class HomePresenter(
                 is HomeEvent.SelectHomeNavigationBarItem -> {
                     currentHomeNavigationBarItemOrdinal = event.item.ordinal
                 }
-                is HomeEvent.SwitchToAccount -> coroutineState.launch {
-                    sessionStore.setLatestSession(event.sessionId.value)
-                }
                 HomeEvent.DismissMultiAccountAnnouncement -> coroutineState.launch {
                     announcementService.onAnnouncementDismissed(Announcement.MultiAccount)
                 }

features/home/impl/src/main/kotlin/io/element/android/features/home/impl/HomeView.kt

@@ -69,6 +69,7 @@ import io.element.android.libraries.designsystem.utils.snackbar.SnackbarHost
 import io.element.android.libraries.designsystem.utils.snackbar.rememberSnackbarHostState
 import io.element.android.libraries.matrix.api.core.EventId
 import io.element.android.libraries.matrix.api.core.RoomId
+import io.element.android.libraries.matrix.api.core.SessionId
 import io.element.android.libraries.ui.strings.CommonStrings
 import kotlinx.coroutines.launch
 
@@ -78,6 +79,7 @@ fun HomeView(
     onRoomClick: (RoomId, EventId?) -> Unit,
     onSettingsClick: () -> Unit,
     onAddAccountClick: () -> Unit,
+    onSwitchToAccount: (SessionId) -> Unit,
     onSetUpRecoveryClick: () -> Unit,
     onConfirmRecoveryKeyClick: () -> Unit,
     onStartChatClick: () -> Unit,
@@ -130,6 +132,7 @@ fun HomeView(
             onStartChatClick = { if (firstThrottler.canHandle()) onStartChatClick() },
             onCreateSpaceClick = { if (firstThrottler.canHandle()) onCreateSpaceClick() },
             onMenuActionClick = onMenuActionClick,
+            onSwitchToAccount = onSwitchToAccount,
         )
 
         if (state.globalSearchState.isEnabled) {
@@ -167,6 +170,7 @@ private fun HomeScaffold(
     onStartChatClick: () -> Unit,
     onCreateSpaceClick: () -> Unit,
     onMenuActionClick: (RoomListMenuAction) -> Unit,
+    onSwitchToAccount: (SessionId) -> Unit,
     modifier: Modifier = Modifier,
 ) {
     fun onRoomClick(room: RoomListRoomSummary) {
@@ -213,9 +217,7 @@ private fun HomeScaffold(
                 },
                 onMenuActionClick = onMenuActionClick,
                 onOpenSettings = onOpenSettings,
-                onAccountSwitch = {
-                    state.eventSink(HomeEvent.SwitchToAccount(it))
-                },
+                onAccountSwitch = onSwitchToAccount,
                 scrollBehavior = scrollBehavior,
                 displayFilters = state.displayRoomListFilters,
                 filtersState = roomListState.filtersState,
@@ -379,6 +381,7 @@ internal fun HomeViewPreview(@PreviewParameter(HomeStatePreviewParam::class) sta
         onRoomClick = { _, _ -> },
         onSettingsClick = {},
         onAddAccountClick = {},
+        onSwitchToAccount = {},
         onSetUpRecoveryClick = {},
         onConfirmRecoveryKeyClick = {},
         onStartChatClick = {},
@@ -400,6 +403,7 @@ internal fun HomeViewA11yPreview() = ElementPreview {
         onRoomClick = { _, _ -> },
         onSettingsClick = {},
         onAddAccountClick = {},
+        onSwitchToAccount = {},
         onSetUpRecoveryClick = {},
         onConfirmRecoveryKeyClick = {},
         onStartChatClick = {},

features/home/impl/src/test/kotlin/io/element/android/features/home/impl/DefaultHomeEntryPointTest.kt

@@ -14,6 +14,7 @@ import io.element.android.features.home.api.HomeEntryPoint
 import io.element.android.features.invite.test.declineandblock.FakeDeclineInviteAndBlockEntryPoint
 import io.element.android.libraries.matrix.api.core.EventId
 import io.element.android.libraries.matrix.api.core.RoomId
+import io.element.android.libraries.matrix.api.core.SessionId
 import io.element.android.libraries.matrix.api.room.JoinedRoom
 import io.element.android.libraries.matrix.test.FakeMatrixClient
 import io.element.android.services.analytics.test.FakeAnalyticsService
@@ -53,6 +54,7 @@ class DefaultHomeEntryPointTest : RobolectricTest() {
             override fun navigateToRoomSettings(roomId: RoomId) = lambdaError()
             override fun navigateToBugReport() = lambdaError()
             override fun navigateToAddAccount() = lambdaError()
+            override fun navigateToSession(sessionId: SessionId) = lambdaError()
         }
         val result = entryPoint.createNode(
             parentNode = parentNode,

features/home/impl/src/test/kotlin/io/element/android/features/home/impl/roomlist/RoomListViewTest.kt

@@ -305,6 +305,7 @@ private fun AndroidComposeUiTest<ComponentActivity>.setRoomListView(
             onRoomClick = { roomId, _ -> onRoomClick(roomId) },
             onSettingsClick = onSettingsClick,
             onAddAccountClick = onAddAccountClick,
+            onSwitchToAccount = EnsureNeverCalledWithParam(),
             onSetUpRecoveryClick = onSetUpRecoveryClick,
             onConfirmRecoveryKeyClick = onConfirmRecoveryKeyClick,
             onStartChatClick = onCreateRoomClick,