fix(desktop): hide Insights/Focus + Tasks board, restore Brain Map tab

- Remove Insights (Focus+Insights hub) from the nav rail.
- Tasks always renders the list; the Board view + Board/List toggle are hidden.
- Brain Map returns as a third Memory hub tab (Memories/Conversations/Brain Map).

Compiles clean; ratchet down-adjusted for the trimmed files.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Author: Archit-lal

.github/scripts/product_file_line_count_ratchet_baseline/desktop-swift-mainwindow.json

@@ -4,16 +4,16 @@
     "desktop/macos/Desktop/Sources/MainWindow/Pages/AppsPage.swift": 3643,
     "desktop/macos/Desktop/Sources/MainWindow/Pages/DashboardPage.swift": 4409,
     "desktop/macos/Desktop/Sources/MainWindow/Pages/MemoriesPage.swift": 3298,
-    "desktop/macos/Desktop/Sources/MainWindow/Pages/TasksPage.swift": 5711,
-    "desktop/macos/Desktop/Sources/MainWindow/SidebarView.swift": 1693
+    "desktop/macos/Desktop/Sources/MainWindow/Pages/TasksPage.swift": 5706,
+    "desktop/macos/Desktop/Sources/MainWindow/SidebarView.swift": 1692
   },
   "raise_justifications": {
     "desktop/macos/Desktop/Sources/MainWindow/Components/ChatBubble.swift": "SB redesign: Omi-mark avatar on replies that spins while thinking (so the extra typing-dots indicator is suppressed for Omi's own replies) and tool-call chips gated to the streaming turn only; a component split is tracked follow-up.",
     "desktop/macos/Desktop/Sources/MainWindow/Pages/AppsPage.swift": "Rebase reconciliation applies the pinned swift-format to the main-branch app-detail safety fixes; runtime behavior is unchanged.",
     "desktop/macos/Desktop/Sources/MainWindow/Pages/DashboardPage.swift": "SB redesign: chat-as-home hub with the auto-rotating knows-list (now surfacing learned insights alongside tasks/asks), de-privatized status controls for the persistent top bar, and the post-onboarding opener in the home-chat empty state; a component split is tracked follow-up.",
     "desktop/macos/Desktop/Sources/MainWindow/Pages/MemoriesPage.swift": "Bridge memory search now awaits the active initial or pagination projection before refreshing, preventing an immediate post-navigation marker search from using stale lifecycle capability state.",
     "desktop/macos/Desktop/Sources/MainWindow/Pages/TasksPage.swift": "SB redesign: adds the Notion-style status board (time-bucket columns, task cards with priority/due chips) and Board/List toggle alongside the existing list; a component split is tracked follow-up.",
-    "desktop/macos/Desktop/Sources/MainWindow/SidebarView.swift": "SB redesign: adds the hover-expand AppNavRail (icons→labels) and the merged/simplified navigation (Memory, Insights) driving selectedIndex; a component split is tracked follow-up."
+    "desktop/macos/Desktop/Sources/MainWindow/SidebarView.swift": "SB redesign: adds the hover-expand AppNavRail (icons\u2192labels) and the merged/simplified navigation (Memory, Insights) driving selectedIndex; a component split is tracked follow-up."
   },
   "threshold": 1500
 }

desktop/macos/Desktop/Sources/MainWindow/DesktopHomeView.swift

@@ -1247,9 +1247,9 @@ private struct MemoryHubPage: View {
   var body: some View {
     VStack(spacing: 0) {
       // The "Memory" rail item lands here, so Memories is the default segment;
-      // Conversations (with its live transcript) is second. The Brain Map has
-      // been removed from the UI entirely.
-      HubSegmentedControl(segments: ["Memories", "Conversations"], selection: $segment)
+      // Conversations (with its live transcript) is second, and the Brain Map
+      // graph is its own tab.
+      HubSegmentedControl(segments: ["Memories", "Conversations", "Brain Map"], selection: $segment)
         .padding(.top, 22)
         .padding(.horizontal, 28)
         .padding(.bottom, 4)
@@ -1258,8 +1258,10 @@ private struct MemoryHubPage: View {
         MemoriesPage(
           viewModel: viewModelContainer.memoriesViewModel,
           graphViewModel: viewModelContainer.memoryGraphViewModel)
-      } else {
+      } else if segment == 1 {
         ConversationsPageHost(appState: appState)
+      } else {
+        MemoryGraphPage(viewModel: viewModelContainer.memoryGraphViewModel)
       }
     }
   }

desktop/macos/Desktop/Sources/MainWindow/Pages/TasksPage.swift

@@ -2744,14 +2744,10 @@ struct TasksPage: View {
         && suggestedStore.candidates.isEmpty && !suggestedStore.isLoading
       {
         emptyView
-      } else if tasksViewIsBoard && !viewModel.isInlineCreating {
-        // Notion-style status board: one column per time bucket, tasks as cards.
-        tasksBoardView
       } else {
-        // Render the list view (which hosts the InlineTaskCreationRow) whenever
-        // the user is inline-creating, even if the underlying task list is empty.
-        // Without this guard, clicking "+" on an empty list flips isInlineCreating
-        // but the empty view ignores it, so the input field never appears.
+        // Board view is hidden — Tasks always uses the list. The list view hosts
+        // the InlineTaskCreationRow, so it renders whenever the user is
+        // inline-creating even if the underlying task list is empty.
         tasksListView
       }
     }
@@ -2888,7 +2884,6 @@ struct TasksPage: View {
       .cornerRadius(OmiChrome.elementRadius)
 
       if !viewModel.isMultiSelectMode {
-        viewModeToggle
         completedToggleButton
       } else {
         multiSelectControls

desktop/macos/Desktop/Sources/MainWindow/SidebarView.swift

@@ -1593,14 +1593,13 @@ struct AppNavRail: View {
   }
 
   /// Simplified, merged navigation: "Memory" folds in Conversations + Memories,
-  /// "Focus" folds in Focus + Insights, and Rewind moved off the rail (it opens
-  /// from a right-click on Capture). Each entry drives the shared selectedIndex.
+  /// Rewind moved off the rail (it opens from a right-click on Capture), and
+  /// Insights/Focus are hidden from navigation. Each entry drives selectedIndex.
   private var items: [RailItem] {
     [
       RailItem(index: SidebarNavItem.dashboard.rawValue, title: "Home", icon: "house.fill"),
       RailItem(index: SidebarNavItem.conversations.rawValue, title: "Memory", icon: "brain"),
       RailItem(index: SidebarNavItem.tasks.rawValue, title: "Tasks", icon: "checklist"),
-      RailItem(index: SidebarNavItem.focus.rawValue, title: "Insights", icon: "lightbulb.fill"),
       RailItem(index: SidebarNavItem.apps.rawValue, title: "Apps", icon: "puzzlepiece.fill"),
     ]
   }

desktop/macos/changelog/unreleased/20260722-sb-nav-trim.json

@@ -0,0 +1,3 @@
+{
+  "change": "Second Brain: hide Insights/Focus from navigation, hide the Tasks board view (Tasks is a list), and bring back the Brain Map as its own Memory tab beside Memories and Conversations"
+}