feat(ui): let the user choose and order the bottom bar destinations

sheaf/app/src/main/java/systems/lupine/sheaf/data/repository/PreferencesRepository.kt

@@ -79,6 +79,11 @@ class PreferencesRepository @Inject constructor(
         //    account; "auto" = pin this device to its own clock; else an IANA zone.
         val KEY_ACCOUNT_TIMEZONE = stringPreferencesKey("account_timezone")
         val KEY_TIMEZONE_OVERRIDE = stringPreferencesKey("timezone_override")
+        // Which destinations the user pinned to the bottom bar, in order, as
+        // newline-separated routes. Per-device like the theme override: which
+        // three things you want under your thumb is an ergonomics choice about
+        // this phone, not an account setting. Absent = the seeded defaults.
+        val KEY_NAV_PINS = stringPreferencesKey("nav_pins")
     }
 
     val baseUrl: Flow<String?> = context.dataStore.data.map { it[KEY_BASE_URL] }
@@ -101,6 +106,11 @@ class PreferencesRepository @Inject constructor(
     val historyPageSize: Flow<Int> = context.dataStore.data.map { it[KEY_HISTORY_PAGE_SIZE] ?: 50 }
     val accountTimezone: Flow<String?> = context.dataStore.data.map { it[KEY_ACCOUNT_TIMEZONE] }
     val timezoneOverride: Flow<String?> = context.dataStore.data.map { it[KEY_TIMEZONE_OVERRIDE] }
+    // null means "never chosen" (the nav layer seeds its defaults); an empty
+    // list is a real choice to pin nothing, and is kept distinct from it.
+    val navPins: Flow<List<String>?> = context.dataStore.data.map { prefs ->
+        prefs[KEY_NAV_PINS]?.lines()?.filter { it.isNotBlank() }
+    }
 
     suspend fun saveBaseUrl(url: String) {
         context.dataStore.edit { it[KEY_BASE_URL] = normalizeBaseUrl(url) }
@@ -198,6 +208,15 @@ class PreferencesRepository @Inject constructor(
         context.dataStore.edit { it[KEY_HISTORY_PAGE_SIZE] = size }
     }
 
+    suspend fun saveNavPins(routes: List<String>) {
+        context.dataStore.edit { it[KEY_NAV_PINS] = routes.joinToString("\n") }
+    }
+
+    /** Forget the user's pins so the bar falls back to the seeded defaults. */
+    suspend fun clearNavPins() {
+        context.dataStore.edit { it.remove(KEY_NAV_PINS) }
+    }
+
     suspend fun clearTokens() {
         context.dataStore.edit {
             it.remove(KEY_ACCESS_TOKEN)

sheaf/app/src/main/java/systems/lupine/sheaf/ui/SheafApp.kt

@@ -39,7 +39,10 @@ import systems.lupine.sheaf.ui.journals.JournalDetailScreen
 import systems.lupine.sheaf.ui.journals.JournalsScreen
 import systems.lupine.sheaf.ui.home.HomeScreen
 import systems.lupine.sheaf.ui.navigation.AppDrawerContent
+import systems.lupine.sheaf.ui.navigation.NavPinsScreen
+import systems.lupine.sheaf.ui.navigation.NavPinsViewModel
 import systems.lupine.sheaf.ui.navigation.drawerRoutes
+import systems.lupine.sheaf.ui.navigation.homeDest
 import systems.lupine.sheaf.ui.members.MemberDetailScreen
 import systems.lupine.sheaf.ui.members.MemberProfileScreen
 import systems.lupine.sheaf.ui.members.MembersScreen
@@ -114,6 +117,7 @@ object Routes {
     const val SETTINGS_ACCOUNT       = "settings/account"
     const val SETTINGS_ADMIN_ACTIVITY = "settings/account/admin-activity"
     const val SETTINGS_APPEARANCE    = "settings/appearance"
+    const val SETTINGS_NAV_BAR       = "settings/appearance/nav-bar"
     const val SETTINGS_NOTIFICATIONS = "settings/notifications"
     const val SETTINGS_SERVER        = "settings/server"
     const val SETTINGS_SYSTEM        = "settings/sys"
@@ -161,30 +165,19 @@ private val MAX_CONTENT_WIDTH = 840.dp
 // it gets (so capping it would just cost columns).
 private val FULL_BLEED_ROUTES = setOf(Routes.RELATIONSHIP_GRAPH, Routes.HOME)
 
-// The fast path, not the whole app: Home plus three destinations, with a
-// "More" entry alongside them that opens the drawer. Everything else (Polls,
-// Analytics, Reminders, Relationships, Files, ...) lives in the drawer, which
-// is the complete list.
-val topLevelDestinations = listOf(
-    TopLevelDest(Routes.HOME,     "Home",     Icons.Filled.Home,                  Icons.Outlined.Home),
-    TopLevelDest(Routes.PEOPLE,   "Members",  Icons.Filled.People,                Icons.Outlined.People),
-    TopLevelDest(Routes.HISTORY,  "History",  Icons.Filled.History,               Icons.Outlined.History),
-    TopLevelDest(Routes.JOURNALS, "Journals", Icons.AutoMirrored.Filled.MenuBook, Icons.AutoMirrored.Outlined.MenuBook),
-)
-
-// Destinations that keep the bar/rail on screen: the bar's own four, plus
-// everything reachable from the drawer. Without the drawer routes here,
-// stepping to a drawer destination would drop the app chrome and strand the
-// user on a screen with no way back but the system back gesture.
-private val chromeRoutes: Set<String> =
-    topLevelDestinations.mapTo(mutableSetOf()) { it.route } + drawerRoutes
+// Destinations that keep the bar/rail on screen: everything the drawer can
+// reach, which is a superset of whatever is currently pinned to the bar.
+// Without this, stepping to a drawer destination would drop the app chrome and
+// strand the user on a screen with no way back but the system back gesture.
+private val chromeRoutes: Set<String> = drawerRoutes
 
 // ── Root composable ───────────────────────────────────────────────────────────
 
 @Composable
 fun SheafApp(
     pendingRedemption: PendingRedemptionHolder,
     authViewModel: AuthViewModel = hiltViewModel(),
+    navPinsViewModel: NavPinsViewModel = hiltViewModel(),
 ) {
     val isLoggedIn by authViewModel.isLoggedIn.collectAsState()
     val pendingRedeem by pendingRedemption.pending.collectAsState()
@@ -248,6 +241,10 @@ fun SheafApp(
         else -> NavigationSuiteType.NavigationBar
     }
 
+    // Home owns the first slot always; the rest are the user's pins.
+    val pinned by navPinsViewModel.pins.collectAsState()
+    val barDestinations = remember(pinned) { listOf(homeDest) + pinned }
+
     val drawerState = rememberDrawerState(DrawerValue.Closed)
     val scope = rememberCoroutineScope()
     // Switching top-level destination is a "start over here" move, not a step
@@ -280,14 +277,14 @@ fun SheafApp(
     NavigationSuiteScaffold(
         layoutType = navSuiteType,
         navigationSuiteItems = {
-            topLevelDestinations.forEach { dest ->
+            barDestinations.forEach { dest ->
                 val selected = currentDest?.hierarchy?.any { it.route == dest.route } == true
                 item(
                     selected = selected,
                     onClick = { goTo(dest.route) },
                     icon = {
                         Icon(
-                            if (selected) dest.selectedIcon else dest.unselectedIcon,
+                            if (selected) dest.selectedIcon else dest.icon,
                             contentDescription = dest.label,
                         )
                     },
@@ -299,7 +296,7 @@ fun SheafApp(
             // still shows where you are.
             val onDrawerDest = currentRoute != null &&
                 currentRoute in drawerRoutes &&
-                topLevelDestinations.none { it.route == currentRoute }
+                barDestinations.none { it.route == currentRoute }
             item(
                 selected = onDrawerDest,
                 onClick = { scope.launch { drawerState.open() } },
@@ -352,8 +349,6 @@ fun SheafApp(
                     onNavigateToSystemSafety = { navController.navigate(Routes.SYSTEM_SAFETY) },
                     onNavigateToRetention = { navController.navigate(Routes.SETTINGS_RETENTION) },
                     onNavigateToSettings = { navController.navigate(Routes.SETTINGS) },
-                    onNavigateToMessages = { navController.navigate(Routes.MESSAGES) },
-                    onNavigateToNotifications = { navController.navigate(Routes.SETTINGS_NOTIFICATIONS) },
                 )
             }
             composable(Routes.PEOPLE) {
@@ -472,8 +467,12 @@ fun SheafApp(
             composable(Routes.SETTINGS_APPEARANCE) {
                 systems.lupine.sheaf.ui.settings.AppearanceSettingsScreen(
                     onNavigateUp = { navController.navigateUp() },
+                    onNavigateToNavBar = { navController.navigate(Routes.SETTINGS_NAV_BAR) },
                 )
             }
+            composable(Routes.SETTINGS_NAV_BAR) {
+                NavPinsScreen(onNavigateUp = { navController.navigateUp() })
+            }
             composable(Routes.SETTINGS_NOTIFICATIONS) {
                 systems.lupine.sheaf.ui.settings.NotificationSettingsScreen(
                     onNavigateUp = { navController.navigateUp() },

sheaf/app/src/main/java/systems/lupine/sheaf/ui/home/HomeScreen.kt

@@ -55,8 +55,6 @@ fun HomeScreen(
     onNavigateToSystemSafety: () -> Unit,
     onNavigateToRetention: () -> Unit,
     onNavigateToSettings: () -> Unit,
-    onNavigateToMessages: () -> Unit,
-    onNavigateToNotifications: () -> Unit,
     viewModel: HomeViewModel = hiltViewModel(),
     authViewModel: AuthViewModel = hiltViewModel(),
 ) {
@@ -93,20 +91,9 @@ fun HomeScreen(
                     )
                 },
                 actions = {
-                    IconButton(onClick = onNavigateToMessages) {
-                        Icon(Icons.Outlined.Forum, contentDescription = "Board messages")
-                    }
-                    // Notifications hub on the top bar: same parity with
-                    // web's sidebar (notifications is a first-class entry,
-                    // not buried two taps into Settings). One tap from
-                    // Home reaches owned channels, your subscriptions,
-                    // your devices, and reminders.
-                    IconButton(onClick = onNavigateToNotifications) {
-                        Icon(
-                            Icons.Outlined.Notifications,
-                            contentDescription = "Notifications",
-                        )
-                    }
+                    // Board messages and Notifications used to sit here too.
+                    // The drawer lists both now, so the top bar doesn't need to
+                    // carry the overflow that the bottom bar couldn't hold.
                     IconButton(onClick = onNavigateToSettings) {
                         Icon(Icons.Default.Settings, contentDescription = "Settings")
                     }

sheaf/app/src/main/java/systems/lupine/sheaf/ui/navigation/AppDrawer.kt

@@ -1,25 +1,16 @@
 package systems.lupine.sheaf.ui.navigation
 
+import androidx.compose.foundation.layout.Column
 import androidx.compose.foundation.layout.Spacer
 import androidx.compose.foundation.layout.height
 import androidx.compose.foundation.layout.padding
 import androidx.compose.foundation.rememberScrollState
 import androidx.compose.foundation.verticalScroll
 import androidx.compose.material.icons.Icons
+import androidx.compose.material.icons.automirrored.filled.MenuBook
 import androidx.compose.material.icons.automirrored.outlined.MenuBook
-import androidx.compose.material.icons.outlined.Alarm
-import androidx.compose.material.icons.outlined.Folder
-import androidx.compose.material.icons.outlined.FolderOpen
-import androidx.compose.material.icons.outlined.Forum
-import androidx.compose.material.icons.outlined.HelpOutline
-import androidx.compose.material.icons.outlined.History
-import androidx.compose.material.icons.outlined.Home
-import androidx.compose.material.icons.outlined.HowToVote
-import androidx.compose.material.icons.outlined.Hub
-import androidx.compose.material.icons.outlined.Insights
-import androidx.compose.material.icons.outlined.Notifications
-import androidx.compose.material.icons.outlined.People
-import androidx.compose.material.icons.outlined.Settings
+import androidx.compose.material.icons.filled.*
+import androidx.compose.material.icons.outlined.*
 import androidx.compose.material3.HorizontalDivider
 import androidx.compose.material3.Icon
 import androidx.compose.material3.MaterialTheme
@@ -33,11 +24,16 @@ import androidx.compose.ui.graphics.vector.ImageVector
 import androidx.compose.ui.unit.dp
 import systems.lupine.sheaf.ui.Routes
 
-/** A single destination row in the navigation drawer. */
+/**
+ * A destination the user can navigate to from the drawer, and (Home aside) pin
+ * to the bottom bar. [selectedIcon] is the filled variant shown when the bar
+ * slot is the current destination; it falls back to the outlined one.
+ */
 data class DrawerDest(
     val route: String,
     val label: String,
     val icon: ImageVector,
+    val selectedIcon: ImageVector = icon,
 )
 
 /** A titled cluster of drawer rows. A null title renders with no header. */
@@ -46,6 +42,9 @@ data class DrawerGroup(
     val items: List<DrawerDest>,
 )
 
+/** Home is the fixed first slot: not movable, not removable, always present. */
+val homeDest = DrawerDest(Routes.HOME, "Home", Icons.Outlined.Home, Icons.Filled.Home)
+
 /**
  * The complete destination list, grouped. This is the Android expression of
  * web's sidebar: the bottom bar / rail is only a fast path to a few of these,
@@ -57,52 +56,100 @@ data class DrawerGroup(
 val drawerGroups: List<DrawerGroup> = listOf(
     DrawerGroup(
         title = null,
-        items = listOf(
-            DrawerDest(Routes.HOME, "Home", Icons.Outlined.Home),
-        ),
+        items = listOf(homeDest),
     ),
     DrawerGroup(
         title = "Tracking",
         items = listOf(
-            DrawerDest(Routes.PEOPLE, "Members", Icons.Outlined.People),
-            DrawerDest(Routes.GROUPS, "Groups", Icons.Outlined.FolderOpen),
-            DrawerDest(Routes.HISTORY, "Front history", Icons.Outlined.History),
-            DrawerDest(Routes.ANALYTICS, "Analytics", Icons.Outlined.Insights),
+            DrawerDest(Routes.PEOPLE, "Members", Icons.Outlined.People, Icons.Filled.People),
+            DrawerDest(Routes.GROUPS, "Groups", Icons.Outlined.FolderOpen, Icons.Filled.FolderOpen),
+            DrawerDest(Routes.HISTORY, "Front history", Icons.Outlined.History, Icons.Filled.History),
+            DrawerDest(Routes.ANALYTICS, "Analytics", Icons.Outlined.Insights, Icons.Filled.Insights),
         ),
     ),
     DrawerGroup(
         title = "Writing",
         items = listOf(
-            DrawerDest(Routes.JOURNALS, "Journals", Icons.AutoMirrored.Outlined.MenuBook),
-            DrawerDest(Routes.MESSAGES, "Board messages", Icons.Outlined.Forum),
+            DrawerDest(
+                Routes.JOURNALS,
+                "Journals",
+                Icons.AutoMirrored.Outlined.MenuBook,
+                Icons.AutoMirrored.Filled.MenuBook,
+            ),
+            DrawerDest(Routes.MESSAGES, "Board messages", Icons.Outlined.Forum, Icons.Filled.Forum),
         ),
     ),
     DrawerGroup(
         title = "Engage",
         items = listOf(
-            DrawerDest(Routes.POLLS, "Polls", Icons.Outlined.HowToVote),
-            DrawerDest(Routes.NOTIFICATIONS_REMINDERS, "Reminders", Icons.Outlined.Alarm),
+            DrawerDest(Routes.POLLS, "Polls", Icons.Outlined.HowToVote, Icons.Filled.HowToVote),
+            DrawerDest(
+                Routes.NOTIFICATIONS_REMINDERS,
+                "Reminders",
+                Icons.Outlined.Alarm,
+                Icons.Filled.Alarm,
+            ),
         ),
     ),
     DrawerGroup(
         title = "System",
         items = listOf(
-            DrawerDest(Routes.RELATIONSHIPS, "Relationships", Icons.Outlined.Hub),
-            DrawerDest(Routes.FILES, "Files", Icons.Outlined.Folder),
+            DrawerDest(Routes.RELATIONSHIPS, "Relationships", Icons.Outlined.Hub, Icons.Filled.Hub),
+            DrawerDest(Routes.FILES, "Files", Icons.Outlined.Folder, Icons.Filled.Folder),
         ),
     ),
     DrawerGroup(
         title = null,
         items = listOf(
-            DrawerDest(Routes.SETTINGS_NOTIFICATIONS, "Notifications", Icons.Outlined.Notifications),
+            DrawerDest(
+                Routes.SETTINGS_NOTIFICATIONS,
+                "Notifications",
+                Icons.Outlined.Notifications,
+                Icons.Filled.Notifications,
+            ),
             DrawerDest(Routes.SUPPORT, "Support", Icons.Outlined.HelpOutline),
-            DrawerDest(Routes.SETTINGS, "Settings", Icons.Outlined.Settings),
+            DrawerDest(Routes.SETTINGS, "Settings", Icons.Outlined.Settings, Icons.Filled.Settings),
         ),
     ),
 )
 
+/** Every destination, flattened. */
+val allDests: List<DrawerDest> = drawerGroups.flatMap { it.items }
+
 /** Every route the drawer can reach, for chrome / selection decisions. */
-val drawerRoutes: Set<String> = drawerGroups.flatMap { group -> group.items.map { it.route } }.toSet()
+val drawerRoutes: Set<String> = allDests.mapTo(mutableSetOf()) { it.route }
+
+/** Everything the user may pin. Home is excluded: it owns the first slot. */
+val pinnableDests: List<DrawerDest> = allDests.filter { it.route != Routes.HOME }
+
+/** How many slots sit between Home and the More entry. */
+const val PIN_SLOTS = 3
+
+/** What a fresh install pins, before the user says otherwise. */
+val DEFAULT_PINS: List<String> = listOf(Routes.PEOPLE, Routes.HISTORY, Routes.JOURNALS)
+
+/**
+ * Turn saved pin routes into the destinations the bar should show.
+ *
+ * [saved] is null when the user has never chosen, which seeds [DEFAULT_PINS];
+ * an empty list is a real choice (bar of just Home and More) and is honoured as
+ * one. Short lists are left short rather than topped up: padding would mean
+ * unpinning something in the editor silently put a different destination in its
+ * place, so the bar and the editor would disagree about what is pinned.
+ *
+ * Saved pins outlive the build that wrote them, so the routes are treated as
+ * untrusted: unknown ones (a destination renamed or dropped in a later version)
+ * are discarded rather than rendered as a dead slot, and duplicates collapse.
+ * Home is never included; it is prepended by the caller.
+ */
+fun resolvePins(saved: List<String>?): List<DrawerDest> {
+    val byRoute = pinnableDests.associateBy { it.route }
+    val chosen = LinkedHashMap<String, DrawerDest>()
+    (saved ?: DEFAULT_PINS).forEach { route ->
+        byRoute[route]?.let { chosen.putIfAbsent(route, it) }
+    }
+    return chosen.values.take(PIN_SLOTS)
+}
 
 /**
  * Drawer body: the grouped destination list. Scrolls, because the list is
@@ -114,9 +161,7 @@ fun AppDrawerContent(
     onNavigate: (String) -> Unit,
 ) {
     ModalDrawerSheet {
-        androidx.compose.foundation.layout.Column(
-            modifier = Modifier.verticalScroll(rememberScrollState()),
-        ) {
+        Column(modifier = Modifier.verticalScroll(rememberScrollState())) {
             Text(
                 text = "Sheaf",
                 style = MaterialTheme.typography.titleLarge,