feat: add PostHog analytics with full event tracking across app

Integrate self-hosted PostHog (SPM) with AnalyticsManager singleton wrapping
all SDK calls. Adds ~40 type-safe events covering trip planning, schedule,
progress, IAP, settings, polls, export, and share flows. Includes session
replay, autocapture, network telemetry, privacy opt-out toggle in Settings,
and super properties (app version, device, pro status, selected sports).

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

SportsTime/Features/Paywall/Views/OnboardingPaywallView.swift

@@ -477,6 +477,9 @@ struct OnboardingPaywallView: View {
                 .padding(.bottom, Theme.Spacing.xl)
         }
         .background(Theme.backgroundGradient(colorScheme))
+        .onAppear {
+            AnalyticsManager.shared.track(.onboardingPaywallViewed)
+        }
     }
 
     // MARK: - Feature Page
@@ -556,7 +559,7 @@ struct OnboardingPaywallView: View {
     // MARK: - Pricing Page
 
     private var pricingPage: some View {
-        PaywallView()
+        PaywallView(source: "onboarding")
             .storeButton(.hidden, for: .cancellation)
     }
 
@@ -584,6 +587,7 @@ struct OnboardingPaywallView: View {
             // Continue free (always visible)
             Button {
                 markOnboardingSeen()
+                AnalyticsManager.shared.track(.onboardingPaywallDismissed)
                 isPresented = false
             } label: {
                 Text("Continue with Free")

SportsTime/Features/Paywall/Views/PaywallView.swift

@@ -13,6 +13,11 @@ struct PaywallView: View {
     @Environment(\.colorScheme) private var colorScheme
 
     private let storeManager = StoreManager.shared
+    let source: String
+
+    init(source: String = "unknown") {
+        self.source = source
+    }
 
     var body: some View {
         SubscriptionStoreView(subscriptions: storeManager.products.filter { $0.subscription != nil }) {
@@ -41,14 +46,34 @@ struct PaywallView: View {
         .storeButton(.visible, for: .restorePurchases)
         .subscriptionStoreControlStyle(.prominentPicker)
         .subscriptionStoreButtonLabel(.displayName.multiline)
-        .onInAppPurchaseCompletion { _, result in
-            if case .success(.success) = result {
+        .onInAppPurchaseStart { product in
+            AnalyticsManager.shared.trackPurchaseStarted(productId: product.id, source: source)
+        }
+        .onInAppPurchaseCompletion { product, result in
+            switch result {
+            case .success(.success(_)):
+                AnalyticsManager.shared.trackPurchaseCompleted(productId: product.id, source: source)
+                Task { @MainActor in
+                    await storeManager.updateEntitlements()
+                    storeManager.trackSubscriptionAnalytics(source: "purchase_success")
+                }
                 dismiss()
+            case .success(.userCancelled):
+                AnalyticsManager.shared.trackPurchaseFailed(productId: product.id, source: source, error: "user_cancelled")
+            case .success(.pending):
+                AnalyticsManager.shared.trackPurchaseFailed(productId: product.id, source: source, error: "pending")
+            case .failure(let error):
+                AnalyticsManager.shared.trackPurchaseFailed(productId: product.id, source: source, error: error.localizedDescription)
+            @unknown default:
+                AnalyticsManager.shared.trackPurchaseFailed(productId: product.id, source: source, error: "unknown_result")
             }
         }
         .task {
             await storeManager.loadProducts()
         }
+        .onAppear {
+            AnalyticsManager.shared.trackPaywallViewed(source: source)
+        }
     }
 
     private func featurePill(icon: String, text: String) -> some View {