Add Insights tab with 60+ randomized analytics

New Insights tab between Year and Customize with:
- 20 insight generators producing 60+ unique insights
- 5 random insights selected per section (month, year, all-time)
- Categories: dominant mood, streaks, trends, positivity score,
  weekend vs weekday, mood swings, milestones, patterns, and more
- Collapsible sections with mood-colored cards
- Subscription paywall support
- English and Spanish localization

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Shared/Views/MainTabView.swift

@@ -19,25 +19,31 @@ struct MainTabView: View {
     let dayView: DayView
     let monthView: MonthView
     let yearView: YearView
+    let insightsView: InsightsView
     let customizeView: CustomizeView
-    
+
     var body: some View {
         return TabView {
             dayView
                 .tabItem {
                     Label(String(localized: "content_view_tab_main"), systemImage: "list.dash")
                 }
-            
+
             monthView
                 .tabItem {
                     Label(String(localized: "content_view_tab_month"), systemImage: "calendar")
                 }
-            
+
            yearView
                 .tabItem {
                     Label(String(localized: "content_view_tab_filter"), systemImage: "line.3.horizontal.decrease.circle")
                 }
-            
+
+            insightsView
+                .tabItem {
+                    Label(String(localized: "content_view_tab_insights"), systemImage: "lightbulb.fill")
+                }
+
             customizeView
                 .tabItem {
                     Label(String(localized: "content_view_tab_customize"), systemImage: "pencil")
@@ -81,8 +87,9 @@ struct MainTabView: View {
 struct MainTabView_Previews: PreviewProvider {
     static var previews: some View {
         MainTabView(dayView: DayView(viewModel: DayViewViewModel(addMonthStartWeekdayPadding: false)),
-                    monthView:  MonthView(viewModel: DayViewViewModel(addMonthStartWeekdayPadding: true)),
+                    monthView: MonthView(viewModel: DayViewViewModel(addMonthStartWeekdayPadding: true)),
                     yearView: YearView(viewModel: YearViewModel()),
+                    insightsView: InsightsView(),
                     customizeView: CustomizeView())
     }
 }