feat(#43): Downgrade App Lifecycle and Navigation Framework

.gitea/workflows/build.yml

@@ -12,7 +12,7 @@ concurrency:
 jobs:
   build-and-test:
     name: Build & Test (Intel x86_64)
-    runs-on: macos-14
+    runs-on: macos-12
 
     steps:
       - name: Check out repository
@@ -78,7 +78,7 @@ jobs:
   release-package:
     name: Package Release Artifact
     needs: build-and-test
-    runs-on: macos-14
+    runs-on: macos-12
     if: startsWith(github.ref, 'refs/tags/v')
 
     steps:

.gitignore

@@ -25,3 +25,7 @@ xcuserdata/
 *.dmg
 *.zip
 *.app
+FIRST-PASS-REFERENCE.md
+SECOND-PASS-REFERENCE.md
+Docs/AppleSilicon-plan.md
+Docs/Monterey-plan.md

BUILD-PLAN.md

@@ -3,7 +3,7 @@
 ## 1. Project Specifications & Architectural Constraints
 
 - **Platform Target:** macOS for Intel (`x86_64`).
-- **Minimum OS Version:** macOS 14.0 (Sonoma) or higher.
+- **Minimum OS Version:** macOS 12.0 (Monterey) or higher.
 - **Language Stack:** SwiftUI (Presentation & ViewModels) + Objective-C / C (Low-level Mach, IOKit, SMC, BSD Sysctl APIs).
 - **Interoperability:** Modular Objective-C bridging layer (`MacMonitor-Bridging-Header.h`) exposing thread-safe C primitives to Swift.
 - **CI/CD Platform:** Gitea Actions executing on Intel macOS runners (`[macos, intel]`).
@@ -144,7 +144,7 @@ graph TD
   2. **Phase 1.2 (Parallel Tracks):**
      - **Track 1.2A:** `#2` AppleSMC Client (`feat/2-smc-client`). Low-level SMC key reader, data parsers (`sp78`, `fpe2`, `flt`).
      - **Track 1.2B:** `#25` Gitea CI/CD Pipeline (`feat/25-gitea-ci`). Create `.gitea/workflows/build.yml` targeting Intel runners.
-- **Quality Gate M1:** Successful build and execution of sample test suite on Gitea Actions runner compiling for `x86_64` macOS 14.
+- **Quality Gate M1:** Successful build and execution of sample test suite on Gitea Actions runner compiling for `x86_64` macOS 12.
 
 ---
 
@@ -189,7 +189,7 @@ graph TD
 
 ### Milestone 4: Presentation, Visuals & Menu Bar Integration
 - **Integration Branch:** `milestone/m4-presentation`
-- **Goal:** User-facing presentation layer: macOS 14 Menu Bar Extra, popover widgets, display brightness management, and Swift Charts rolling graphs.
+- **Goal:** User-facing presentation layer: macOS 12 Menu Bar Extra, popover widgets, display brightness management, and Swift Charts rolling graphs.
 - **Execution Order:**
   1. `#13` Screen Brightness & Display Management (`feat/13-display-brightness`)
   2. `#22` Status Bar Menu Bar Extra & Popover (`feat/22-menubar-popover`)

MacMonitor.xcodeproj/project.pbxproj

@@ -698,7 +698,7 @@
 					"$(inherited)",
 					"@executable_path/../Frameworks",
 				);
-				MACOSX_DEPLOYMENT_TARGET = 14.0;
+				MACOSX_DEPLOYMENT_TARGET = 12.0;
 				PRODUCT_BUNDLE_IDENTIFIER = com.i3omb.MacMonitor;
 				SDKROOT = macosx;
 				SWIFT_OBJC_BRIDGING_HEADER = "Sources/Bridging/MacMonitor-Bridging-Header.h";
@@ -720,7 +720,7 @@
 					"@executable_path/../Frameworks",
 					"@loader_path/../Frameworks",
 				);
-				MACOSX_DEPLOYMENT_TARGET = 14.0;
+				MACOSX_DEPLOYMENT_TARGET = 12.0;
 				PRODUCT_BUNDLE_IDENTIFIER = com.i3omb.MacMonitorTests;
 				SDKROOT = macosx;
 				SWIFT_OBJC_BRIDGING_HEADER = "Sources/Bridging/MacMonitor-Bridging-Header.h";
@@ -778,7 +778,7 @@
 				GCC_WARN_UNUSED_FUNCTION = YES;
 				GCC_WARN_UNUSED_VARIABLE = YES;
 				GENERATE_INFOPLIST_FILE = YES;
-				MACOSX_DEPLOYMENT_TARGET = 14.0;
+				MACOSX_DEPLOYMENT_TARGET = 12.0;
 				MARKETING_VERSION = 0.0.2;
 				MTL_ENABLE_DEBUG_INFO = NO;
 				MTL_FAST_MATH = YES;
@@ -807,7 +807,7 @@
 					"@executable_path/../Frameworks",
 					"@loader_path/../Frameworks",
 				);
-				MACOSX_DEPLOYMENT_TARGET = 14.0;
+				MACOSX_DEPLOYMENT_TARGET = 12.0;
 				PRODUCT_BUNDLE_IDENTIFIER = com.i3omb.MacMonitorTests;
 				SDKROOT = macosx;
 				SWIFT_OBJC_BRIDGING_HEADER = "Sources/Bridging/MacMonitor-Bridging-Header.h";
@@ -871,7 +871,7 @@
 				GCC_WARN_UNUSED_FUNCTION = YES;
 				GCC_WARN_UNUSED_VARIABLE = YES;
 				GENERATE_INFOPLIST_FILE = YES;
-				MACOSX_DEPLOYMENT_TARGET = 14.0;
+				MACOSX_DEPLOYMENT_TARGET = 12.0;
 				MARKETING_VERSION = 0.0.2;
 				MTL_ENABLE_DEBUG_INFO = INCLUDE_SOURCE;
 				MTL_FAST_MATH = YES;
@@ -902,7 +902,7 @@
 					"$(inherited)",
 					"@executable_path/../Frameworks",
 				);
-				MACOSX_DEPLOYMENT_TARGET = 14.0;
+				MACOSX_DEPLOYMENT_TARGET = 12.0;
 				PRODUCT_BUNDLE_IDENTIFIER = com.i3omb.MacMonitor;
 				SDKROOT = macosx;
 				SWIFT_OBJC_BRIDGING_HEADER = "Sources/Bridging/MacMonitor-Bridging-Header.h";

Sources/App/MacMonitorApp.swift

@@ -1,19 +1,66 @@
 import SwiftUI
+import Combine
 
 /// Bridges app-lifecycle events into SwiftUI: requests Notification Center
 /// authorization once at launch so threshold alerts can post banners.
 final class AppDelegate: NSObject, NSApplicationDelegate {
+    var statusItem: NSStatusItem?
+    var popover: NSPopover?
+    var cancellable: AnyCancellable?
+
     func applicationDidFinishLaunching(_ notification: Notification) {
         if AlertEngine.shared.configuration.alertsEnabled {
             AlertEngine.shared.requestNotificationAuthorization()
         }
+        setupMenuBar()
+    }
+    
+    private func setupMenuBar() {
+        statusItem = NSStatusBar.system.statusItem(withLength: NSStatusItem.variableLength)
+        
+        let popover = NSPopover()
+        popover.contentSize = NSSize(width: 320, height: 400)
+        popover.behavior = .transient
+        popover.contentViewController = NSHostingController(rootView: QuickGlancePopoverView(store: SystemTelemetryStore.shared))
+        self.popover = popover
+        
+        if let button = statusItem?.button {
+            button.action = #selector(togglePopover(_:))
+            button.target = self
+        }
+        
+        cancellable = SystemTelemetryStore.shared.$latestSnapshot.sink { [weak self] _ in
+            DispatchQueue.main.async {
+                self?.updateMenuBarLabel()
+            }
+        }
+        updateMenuBarLabel()
+    }
+    
+    @objc func togglePopover(_ sender: AnyObject?) {
+        guard let button = statusItem?.button, let popover = popover else { return }
+        if popover.isShown {
+            popover.performClose(sender)
+        } else {
+            popover.show(relativeTo: button.bounds, of: button, preferredEdge: .minY)
+        }
+    }
+    
+    private func updateMenuBarLabel() {
+        guard let button = statusItem?.button else { return }
+        let cpu = SystemTelemetryStore.shared.cpuLoad.totalLoad
+        let mem = SystemTelemetryStore.shared.memory.utilizationPercentage
+        let alerts = AlertEngine.shared.activeAlerts.count
+        
+        let alertStr = alerts > 0 ? "⚠️ " : ""
+        button.title = String(format: "%@CPU: %.0f%% • RAM: %.0f%%", alertStr, cpu, mem)
     }
 }
 
 @main
 struct MacMonitorApp: App {
     @NSApplicationDelegateAdaptor(AppDelegate.self) private var appDelegate
-    @State private var store = SystemTelemetryStore.shared
+    @StateObject private var store = SystemTelemetryStore.shared
 
     var body: some Scene {
         WindowGroup {
@@ -21,18 +68,6 @@ struct MacMonitorApp: App {
         }
         .windowStyle(.titleBar)
         .windowToolbarStyle(.unified)
-        .defaultSize(width: 960, height: 640)
-
-        MenuBarExtra {
-            QuickGlancePopoverView(store: store)
-        } label: {
-            MenuBarStatusView(
-                cpuLoad: store.cpuLoad.totalLoad,
-                memoryPercent: store.memory.utilizationPercentage,
-                activeAlertCount: store.alertEngine.activeAlerts.count
-            )
-        }
-        .menuBarExtraStyle(.window)
 
         Settings {
             AlertsSettingsView()

Sources/App/SystemTelemetryStore.swift

@@ -1,6 +1,6 @@
 import Foundation
 import SwiftUI
-import Observation
+import Combine
 
 // MARK: - Typed Telemetry Models
 
@@ -220,39 +220,38 @@ public struct AudioDeviceItem: Identifiable, Sendable {
 
 // MARK: - SystemTelemetryStore
 
-@Observable
 @MainActor
-public final class SystemTelemetryStore {
+public final class SystemTelemetryStore: ObservableObject {
     public static let shared = SystemTelemetryStore()
     
-    public private(set) var isRunning: Bool = false
-    public private(set) var lastUpdateTimestamp: Date = .now
-    public private(set) var sampleInterval: TimeInterval = 1.0
+    @Published public private(set) var isRunning: Bool = false
+    @Published public private(set) var lastUpdateTimestamp: Date = .now
+    @Published public private(set) var sampleInterval: TimeInterval = 1.0
     
     /// Raw snapshots organized by provider identifier
-    public private(set) var latestSnapshot: [String: [String: Any]] = [:]
+    @Published public private(set) var latestSnapshot: [String: [String: Any]] = [:]
     
     /// Milestone 2 Structured Metrics
-    public private(set) var cpuLoad = CPULoadMetrics()
-    public private(set) var memory = MemoryMetrics()
-    public private(set) var storageVolumes: [StorageVolumeItem] = []
-    public private(set) var cpuThermal = CPUThermalMetrics()
-    public private(set) var fans: [FanTelemetryItem] = []
-    public private(set) var componentTemps: [ComponentThermalItem] = []
-    public private(set) var power = PowerMetrics()
+    @Published public private(set) var cpuLoad = CPULoadMetrics()
+    @Published public private(set) var memory = MemoryMetrics()
+    @Published public private(set) var storageVolumes: [StorageVolumeItem] = []
+    @Published public private(set) var cpuThermal = CPUThermalMetrics()
+    @Published public private(set) var fans: [FanTelemetryItem] = []
+    @Published public private(set) var componentTemps: [ComponentThermalItem] = []
+    @Published public private(set) var power = PowerMetrics()
     
     /// Milestone 3 Structured Metrics
-    public private(set) var kernelCounters = KernelCountersMetrics()
-    public private(set) var systemLoad = SystemLoadMetrics()
-    public private(set) var diskIO: [DiskIOItem] = []
-    public private(set) var networkBandwidth: [NetworkBandwidthItem] = []
-    public private(set) var networkSockets: [SocketItem] = []
-    public private(set) var processes: [ProcessItem] = []
-    public private(set) var gpus: [GPUCardItem] = []
-    public private(set) var batteryHealth = BatteryHealthMetrics()
-    public private(set) var peripherals: [PeripheralDeviceItem] = []
-    public private(set) var audioDevices: [AudioDeviceItem] = []
-    public private(set) var displays: [MMDisplayInfo] = []
+    @Published public private(set) var kernelCounters = KernelCountersMetrics()
+    @Published public private(set) var systemLoad = SystemLoadMetrics()
+    @Published public private(set) var diskIO: [DiskIOItem] = []
+    @Published public private(set) var networkBandwidth: [NetworkBandwidthItem] = []
+    @Published public private(set) var networkSockets: [SocketItem] = []
+    @Published public private(set) var processes: [ProcessItem] = []
+    @Published public private(set) var gpus: [GPUCardItem] = []
+    @Published public private(set) var batteryHealth = BatteryHealthMetrics()
+    @Published public private(set) var peripherals: [PeripheralDeviceItem] = []
+    @Published public private(set) var audioDevices: [AudioDeviceItem] = []
+    @Published public private(set) var displays: [MMDisplayInfo] = []
     
     /// Historical Telemetry Store
     public let historyStore = TelemetryHistoryStore.shared

Sources/History/TelemetryHistoryStore.swift

@@ -1,5 +1,6 @@
 import Foundation
 import SwiftUI
+import Combine
 
 public struct TelemetrySnapshotRecord {
     public let cpuLoad: Double
@@ -35,8 +36,7 @@ public struct TelemetrySnapshotRecord {
     }
 }
 
-@Observable
-public final class TelemetryHistoryStore {
+public final class TelemetryHistoryStore: ObservableObject {
     public static let shared = TelemetryHistoryStore()
     
     public let cpuHistory = RollingRingBuffer<Double>(capacity: 60)
@@ -48,7 +48,7 @@ public final class TelemetryHistoryStore {
     public let cpuTempHistory = RollingRingBuffer<Double>(capacity: 60)
     public let powerHistory = RollingRingBuffer<Double>(capacity: 60)
     
-    public private(set) var sampleCounter: UInt64 = 0
+    @Published public private(set) var sampleCounter: UInt64 = 0
     
     public init() {}
     

Sources/Intelligence/AlertEngine.swift

@@ -1,5 +1,6 @@
 import Foundation
 import UserNotifications
+import Combine
 
 // MARK: - Alert Engine
 
@@ -13,18 +14,17 @@ import UserNotifications
 ///   persistent   -> re-fire only after `cooldownMinutes` elapse
 ///   recovery     -> remove from active set, log `.resolved`, clear cooldown so
 ///                   the next breach alerts immediately
-@Observable
 @MainActor
-public final class AlertEngine {
+public final class AlertEngine: ObservableObject {
     public static let shared = AlertEngine()
 
     /// Currently breached conditions, refreshed every evaluation pass.
-    public private(set) var activeAlerts: [SystemAlert] = []
+    @Published public private(set) var activeAlerts: [SystemAlert] = []
     /// Newest-first audit log of trigger/resolve events (capped).
-    public private(set) var history: [AlertEvent] = []
+    @Published public private(set) var history: [AlertEvent] = []
 
     /// Threshold settings. Mutations are persisted immediately.
-    public var configuration: AlertConfiguration {
+    @Published public var configuration: AlertConfiguration {
         didSet { configuration.save(to: defaults) }
     }
 

Sources/Intelligence/AlertNotificationDispatcher.swift

@@ -1,20 +1,20 @@
 import Foundation
 import UserNotifications
+import Combine
 
 // MARK: - Navigation Bus
 
 /// Lightweight bus letting notification action handlers steer the main window:
 /// tapping a notification (or its "View Processes" action) activates the app and
 /// selects the requested sidebar tab inside `ContentView`.
-@Observable
-public final class AppNavigationBus {
+public final class AppNavigationBus: ObservableObject {
     public static let shared = AppNavigationBus()
 
     /// Sidebar tag the main window should switch to (e.g. `"Processes"`).
     /// `nil` means "just bring the window forward".
-    public private(set) var requestedTab: String?
+    @Published public private(set) var requestedTab: String?
     /// Monotonic counter so repeated taps on the same tab still trigger `onChange`.
-    public private(set) var requestCounter: Int = 0
+    @Published public private(set) var requestCounter: Int = 0
 
     private init() {}
 

Sources/UI/ContentView.swift

@@ -1,20 +1,19 @@
 import SwiftUI
 
 public struct ContentView: View {
-    @State private var store = SystemTelemetryStore.shared
+    @StateObject private var store = SystemTelemetryStore.shared
     @State private var selectedTab: String = "Dashboard"
     @State private var processSearchText: String = ""
     @State private var socketSearchText: String = ""
     @State private var selectedPID: Int32? = nil
     @State private var showingProcessDetail: Bool = false
-    @State private var navBus = AppNavigationBus.shared
+    @StateObject private var navBus = AppNavigationBus.shared
     
     public init() {}
     
     public var body: some View {
-        NavigationSplitView {
+        NavigationView {
             sidebarContent
-        } detail: {
             detailContent
         }
         .frame(minWidth: 1000, minHeight: 700)
@@ -26,7 +25,7 @@ public struct ContentView: View {
                 ProcessDetailSheet(inspector: store.processInspector, pid: pid)
             }
         }
-        .onChange(of: navBus.requestCounter) { _, _ in
+        .onChange(of: navBus.requestCounter) { _ in
             NSApp.activate(ignoringOtherApps: true)
             if let window = NSApp.windows.first(where: { $0.canBecomeMain }) {
                 window.makeKeyAndOrderFront(nil)
@@ -109,7 +108,7 @@ public struct ContentView: View {
             }
         }
         .listStyle(.sidebar)
-        .navigationSplitViewColumnWidth(min: 210, ideal: 240, max: 300)
+        .frame(minWidth: 210, idealWidth: 240, maxWidth: 300)
     }
     
     // MARK: - Detail Content Router

Sources/UI/Settings/AlertsSettingsView.swift

@@ -6,7 +6,7 @@ import UserNotifications
 /// Preferences UI for threshold alert rules. Bound directly to
 /// `AlertEngine.shared.configuration`, which auto-persists to `UserDefaults`.
 public struct AlertsSettingsView: View {
-    @Bindable private var engine = AlertEngine.shared
+    @ObservedObject private var engine = AlertEngine.shared
     @State private var authorizationStatus: UNAuthorizationStatus = .notDetermined
 
     public init() {}