feat(sidebar): middle-click to close workspace / 中键关闭工作区

Glint/Chrome/SettingsView.swift

@@ -421,6 +421,12 @@ private struct GeneralPane: View {
                 Toggle("", isOn: $store.revealAtRepoRoot)
                     .toggleStyle(.switch).labelsHidden()
             }
+            SettingsDivider()
+            SettingsRow("Middle-click closes workspace",
+                        subtitle: "Click a workspace card with the middle mouse button to close it. Same as the context menu's “Close Workspace”.") {
+                Toggle("", isOn: $store.middleClickClosesWorkspace)
+                    .toggleStyle(.switch).labelsHidden()
+            }
         }
 
         SettingsCard("New terminals") {

Glint/Chrome/SidebarView.swift

@@ -811,6 +811,16 @@ private struct WorkspaceCard: View {
             // than removing it so the call-site stays a single chain.
             including: archived ? .subviews : .all
         )
+        // Middle-click closes the workspace — same path as the context menu's
+        // "Close Workspace" (confirm dialog included when panes are busy).
+        // Disabled while renaming and on archived cards (which expose
+        // Unarchive/Delete instead). Catcher is transparent to left/right/hover
+        // so existing gestures, popover, and menu are untouched.
+        .overlay {
+            if !archived && !isEditing && store.middleClickClosesWorkspace {
+                MiddleClickCatcher { store.deleteWorkspace(ws.id) }
+            }
+        }
     }
 
     private func startEditing() {

Glint/Chrome/VisualEffectBackground.swift

@@ -102,6 +102,50 @@ struct NoDragSurface: NSViewRepresentable {
     }
 }
 
+/// Invisible overlay that fires `onMiddleClick` only on a middle-mouse
+/// button press. Left/right clicks, drags, hover, and scroll pass through
+/// untouched (the view returns nil from `hitTest` unless the middle button
+/// is down), so any SwiftUI gesture / popover / menu underneath keeps
+/// working. Mirror of the `WindowDragSurface` / `NoDragSurface` pattern.
+struct MiddleClickCatcher: NSViewRepresentable {
+    let onMiddleClick: () -> Void
+
+    func makeNSView(context: Context) -> NSView { CatcherView(onMiddleClick: onMiddleClick) }
+    func updateNSView(_ nsView: NSView, context: Context) {
+        (nsView as? CatcherView)?.onMiddleClick = onMiddleClick
+    }
+
+    private final class CatcherView: NSView {
+        var onMiddleClick: () -> Void
+
+        init(onMiddleClick: @escaping () -> Void) {
+            self.onMiddleClick = onMiddleClick
+            super.init(frame: .zero)
+        }
+        @available(*, unavailable) required init?(coder: NSCoder) { fatalError() }
+
+        // Only claim hits when the middle button is pressed — every other
+        // interaction (left/right click, drag, hover, scroll) falls through
+        // to the SwiftUI view underneath. `hitTest` is the gate AppKit
+        // consults before routing any mouse event, so returning nil here
+        // makes this view genuinely transparent to non-middle input.
+        override func hitTest(_ point: NSPoint) -> NSView? {
+            NSEvent.pressedMouseButtons & (1 << 2) != 0 ? self : nil
+        }
+
+        override func otherMouseDown(with event: NSEvent) {
+            // buttonNumber 2 == middle. Other "other" buttons (back/forward)
+            // pass through to the responder chain.
+            guard event.buttonNumber == 2 else { super.otherMouseDown(with: event); return }
+            onMiddleClick()
+        }
+
+        // Never let the overlay drag the window or steal cursor focus.
+        override var mouseDownCanMoveWindow: Bool { false }
+        override var acceptsFirstResponder: Bool { false }
+    }
+}
+
 // MARK: - Liquid Glass (macOS 26)
 
 /// Whether the OS can render Liquid Glass at all. Call sites that keep a

Glint/Resources/Localizable.xcstrings

@@ -2715,6 +2715,28 @@
         }
       }
     },
+    "Middle-click closes workspace": {
+      "extractionState": "manual",
+      "localizations": {
+        "zh-Hans": {
+          "stringUnit": {
+            "state": "translated",
+            "value": "中键关闭工作区"
+          }
+        }
+      }
+    },
+    "Click a workspace card with the middle mouse button to close it. Same as the context menu's \u201cClose Workspace\u201d.": {
+      "extractionState": "manual",
+      "localizations": {
+        "zh-Hans": {
+          "stringUnit": {
+            "state": "translated",
+            "value": "用鼠标中键点击工作区卡片即可关闭,等同于右键菜单的「关闭工作区」。"
+          }
+        }
+      }
+    },
     "Missing": {
       "extractionState": "manual",
       "localizations": {

Glint/Workspace/WorkspaceStore.swift

@@ -1251,6 +1251,14 @@ final class WorkspaceStore: ObservableObject {
         didSet { UserDefaults.standard.set(sortCompletedFirst, forKey: "glint.sortCompletedFirst") }
     }
 
+    /// Middle-click on a workspace card in the sidebar closes it (same path
+    /// as the context menu's "Close Workspace"). Defaults to on so the
+    /// behaviour stays available without configuration; users who find it
+    /// surprising can disable it here.
+    @Published var middleClickClosesWorkspace: Bool = (UserDefaults.standard.object(forKey: "glint.middleClickClosesWorkspace") as? Bool) ?? true {
+        didSet { UserDefaults.standard.set(middleClickClosesWorkspace, forKey: "glint.middleClickClosesWorkspace") }
+    }
+
     /// Show the "Paste potentially unsafe text?" confirm dialog when the
     /// clipboard contains newlines or control characters. The underlying
     /// default (`glint.skipUnsafePasteConfirmation`) is inverted so the