Split the tray into Apps and System sections

Control Center items sat in the same grid as third-party app icons, which
was hard to scan. Group them so Apple's Wi-Fi, Battery, Clock and friends
are listed separately from your apps' icons.

💘 Generated with Crush

Assisted-by: Crush:deepseek-v4.1-flash

Sources/SimpleTopBar/MenuBarItems.swift

@@ -9,6 +9,8 @@ struct MenuBarItem: Identifiable, Equatable {
     let appName: String
     let title: String
     let icon: NSImage
+    /// True for Apple's own items (Control Center, Spotlight, …).
+    let isSystem: Bool
     let element: AXUIElement
 
     static func == (lhs: MenuBarItem, rhs: MenuBarItem) -> Bool {
@@ -91,6 +93,7 @@ final class MenuBarItemManager: ObservableObject {
                     appName: app.localizedName ?? app.bundleIdentifier ?? "Unknown",
                     title: title,
                     icon: Self.icon(forTitle: title, app: app),
+                    isSystem: Self.isSystemBundle(app.bundleIdentifier),
                     element: child
                 ))
             }
@@ -134,6 +137,16 @@ final class MenuBarItemManager: ObservableObject {
         return AXUIElementPerformAction(item.element, kAXShowMenuAction as CFString) == .success
     }
 
+    // MARK: - Classification
+
+    /// Apple's own menu bar items (Control Center, Spotlight, the input-source
+    /// agent, …) live under `com.apple.*` bundles; everything else is a third
+    /// party app.
+    nonisolated static func isSystemBundle(_ bundleID: String?) -> Bool {
+        guard let bundleID else { return false }
+        return bundleID.hasPrefix("com.apple.")
+    }
+
     // MARK: - Icons
 
     /// Picks an icon for a menu bar item. Control Center owns many unrelated