feat: TypeWhisper Flow sessions, Phase 4 UX, and GitHub Pages privacy site

Migrate keyboard dictation to continuous Flow sessions with auto-start,
tap-to-toggle recording, 60s countdown, five-step onboarding, and App Group
IPC. Add docs/ GitHub Pages site with en/zh privacy policy for App Store compliance.

OSGKeyboard/OSGKeyboardApp.swift

@@ -6,14 +6,19 @@ import OSGKeyboardShared
 
 @main
 struct OSGKeyboardApp: App {
+    @Environment(\.scenePhase) private var scenePhase
+
     @StateObject private var config = ProviderConfig.shared
+    @StateObject private var dictationCoordinator = DictationSessionCoordinator()
+    @StateObject private var flowManager = FlowSessionManager()
 
     var body: some Scene {
         WindowGroup {
             ThemedRoot {
                 if AppGroup.isAvailable {
-                    if config.isConfigured {
+                    if config.hasCompletedOnboarding {
                         HomeView()
+                            .onAppear { flowManager.autoStartIfNeeded() }
                     } else {
                         OnboardingView(config: config)
                     }
@@ -21,6 +26,32 @@ struct OSGKeyboardApp: App {
                     AppGroupErrorView()
                 }
             }
+            .environmentObject(flowManager)
+            .onOpenURL { url in
+                guard url.scheme == "osgkeyboard" else { return }
+                switch url.host {
+                case "dictate":
+                    dictationCoordinator.present()
+                case "startflow":
+                    flowManager.startSession()
+                default:
+                    break
+                }
+            }
+            .fullScreenCover(isPresented: $dictationCoordinator.isPresenting) {
+                DictationCaptureView(
+                    config: config,
+                    coordinator: dictationCoordinator
+                )
+            }
+            .onChange(of: scenePhase) { _, phase in
+                guard phase == .active, AppGroup.isAvailable, config.hasCompletedOnboarding else { return }
+                if flowManager.isActive {
+                    flowManager.extendSession()
+                } else {
+                    flowManager.autoStartIfNeeded()
+                }
+            }
         }
     }
-}
+}