Fix iOS toolbar glass and lifecycle

Packages/iOS/CmuxMobileShellUI/Sources/CmuxMobileShellUI/MobileLeadingToolbarTitleWidth.swift

@@ -0,0 +1,29 @@
+import CoreGraphics
+
+/// Width math for the leading glass workspace title menu.
+///
+/// The workspace title belongs beside the back button, not in the centered
+/// principal slot. Reserve the trailing toolbar cluster and the leading back
+/// control so the title truncates before it can underlap native toolbar items.
+struct MobileLeadingToolbarTitleWidth {
+    let contentWidth: CGFloat
+    let hasBackButton: Bool
+    let hasTrailingCluster: Bool
+    let hasChatToggle: Bool
+
+    static let backButtonReserve: CGFloat = 44
+    static let trailingReserveBase: CGFloat = 60
+    static let chatToggleReserve: CGFloat = 56
+    static let barMarginsAndSpacing: CGFloat = 44
+    static let unmeasuredFallback: CGFloat = 180
+    static let floor: CGFloat = 96
+
+    var cap: CGFloat {
+        guard contentWidth > 0 else { return Self.unmeasuredFallback }
+        let leading = hasBackButton ? Self.backButtonReserve : 0
+        let trailing = hasTrailingCluster
+            ? Self.trailingReserveBase + (hasChatToggle ? Self.chatToggleReserve : 0)
+            : 0
+        return max(0, contentWidth - leading - trailing - Self.barMarginsAndSpacing)
+    }
+}

Packages/iOS/CmuxMobileShellUI/Sources/CmuxMobileShellUI/WorkspaceBackButton.swift

@@ -14,8 +14,10 @@ struct WorkspaceBackButton: View {
         Button(action: action) {
             HStack(spacing: 5) {
                 Image(systemName: "chevron.backward")
-                    .fontWeight(.semibold)
+                    .font(.system(size: 17, weight: .semibold))
+                    .imageScale(.medium)
                     .foregroundStyle(.primary)
+                    .frame(width: 17, height: 22)
                 if unreadCount > 0 {
                     Text(countText)
                         // Smaller than the chevron, on a small mono circle.
@@ -27,7 +29,6 @@ struct WorkspaceBackButton: View {
                         .background(badgeFillColor, in: .circle)
                 }
             }
-            .contentShape(.rect)
         }
         .accessibilityLabel(accessibilityLabel)
         .accessibilityIdentifier("MobileWorkspaceBackButton")

Packages/iOS/CmuxMobileShellUI/Sources/CmuxMobileShellUI/WorkspaceChatPane.swift

@@ -12,35 +12,20 @@ import UIKit
 /// The agent chat rendered inline in the workspace detail, in place of the
 /// terminal, when chat mode is toggled on. There is no cover and no Done
 /// button: the same toolbar toggle flips back to the terminal.
-struct WorkspaceChatPane<TitleMenuContent: View>: View {
+struct WorkspaceChatPane: View {
     let session: ChatSessionDescriptor
     let conversation: ChatConversationStore
     let store: CMUXMobileShellStore
-    /// The owning workspace's name, shown as the header title (so the header
-    /// reads as the workspace, not the session's first prompt).
-    let workspaceName: String
-    /// The name of the tab/terminal this session lives on, shown as the
-    /// header subtitle.
-    let tabName: String?
     /// Composer draft, owned by the parent so it survives toggling back to
     /// the terminal and returning mid-thought.
     @Binding var draft: String
-    /// Compact-stack back button owned by the workspace toolbar.
-    let backButtonConfiguration: WorkspaceBackButtonConfiguration?
-    /// Whether the workspace title pill should open a menu.
-    let isTitleMenuEnabled: Bool
-    /// Workspace-scoped actions exposed from the title pill.
-    let titleMenuContent: () -> TitleMenuContent
     /// Flips chat mode off (the toggle's "back to terminal" path).
     let onExitChat: () -> Void
 
     @Environment(BrowserSurfaceStore.self) private var browserStore
 
     @State private var accessoryConfiguration = TerminalAccessoryConfiguration.shared
     @State private var isShowingShortcutSettings = false
-    /// Full content width, used to bound the centered toolbar header so a long
-    /// workspace name truncates before the trailing toolbar buttons.
-    @State private var contentWidth: CGFloat = 0
 
     var body: some View {
         Group {
@@ -53,56 +38,12 @@ struct WorkspaceChatPane<TitleMenuContent: View>: View {
                 runsStoreTask: false,
                 onOpenTerminal: openTerminal
             )
-            // The host (workspace detail) owns the nav bar, so the live
-            // session-state header is supplied here rather than by ChatScreen,
-            // which would be dropped under the workspace's own chrome.
-            .onGeometryChange(for: CGFloat.self) { $0.size.width } action: { contentWidth = $0 }
-            .toolbar {
-                if backButtonConfiguration != nil {
-                    ToolbarItem(placement: .topBarLeading) {
-                        workspaceBackToolbarButton
-                    }
-                }
-                ToolbarItem(placement: .principal) {
-                    // WorkspaceDetailView mounts the terminal picker/chat
-                    // toggle in a sibling trailing toolbar item.
-                    WorkspaceTitleMenu(
-                        contentWidth: contentWidth,
-                        hasBackButton: backButtonConfiguration != nil,
-                        hasTrailingCluster: true,
-                        hasChatToggle: true,
-                        isEnabled: isTitleMenuEnabled,
-                        menuContent: titleMenuContent
-                    ) {
-                        ChatSessionHeaderView(
-                            descriptor: conversation.descriptor,
-                            agentState: conversation.agentState,
-                            isConnected: conversation.isConnected,
-                            titleOverride: workspaceName,
-                            subtitle: tabName,
-                            style: .toolbarCompact
-                        )
-                    }
-                }
-            }
         }
         .sheet(isPresented: $isShowingShortcutSettings) {
             TerminalShortcutsSettingsView(scope: .agentChat)
         }
     }
 
-    @ViewBuilder
-    private var workspaceBackToolbarButton: some View {
-        if let backButtonConfiguration {
-            WorkspaceBackButton(
-                unreadCount: backButtonConfiguration.unreadCount,
-                badgeContrast: backButtonConfiguration.badgeContrast,
-                action: backButtonConfiguration.action
-            )
-            .mobileGlassCompactToolbarControl()
-        }
-    }
-
     /// The escape hatch: select the session's terminal surface, then leave
     /// chat mode so the terminal shows.
     private func openTerminal() {

Packages/iOS/CmuxMobileShellUI/Sources/CmuxMobileShellUI/WorkspaceDetailView+AgentChat.swift

@@ -92,15 +92,10 @@ extension WorkspaceDetailView {
                 session: session,
                 conversation: conversation,
                 store: store,
-                workspaceName: workspace.name,
-                tabName: tabName(for: session),
                 draft: Binding(
                     get: { chatDrafts[session.id] ?? "" },
                     set: { chatDrafts[session.id] = $0 }
                 ),
-                backButtonConfiguration: backButtonConfiguration,
-                isTitleMenuEnabled: hasTitleMenuActions,
-                titleMenuContent: { titleMenuContent },
                 onExitChat: {
                     withAnimation(.snappy(duration: 0.28)) {
                         isChatMode = false
@@ -111,22 +106,6 @@ extension WorkspaceDetailView {
             .id(session.id)
             .frame(maxWidth: .infinity, maxHeight: .infinity)
             .mobileChatTopScrollEdgeLayout(legacyTopPadding: terminalTopPadding)
-            .mobileTerminalNavigationChrome()
-            .toolbar {
-                ToolbarItem(placement: .topBarTrailing) {
-                    toolbarTrailingCluster
-                }
-            }
-            .task(id: chatRefreshKey) { await refreshChatSessions() }
-            .closeWorkspaceConfirmation(
-                isPresented: $isConfirmingClose,
-                confirm: confirmCloseWorkspaceFromMenu
-            )
-            .workspaceRenameDialog(
-                isPresented: $isRenamePresented,
-                text: $renameText,
-                onSave: commitRenameFromDialog
-            )
         } else {
             Color.clear
                 .task(id: session.id) {