Update onboarding statistics with verified sources

- Replace fabricated stats with real data from industry surveys
- 60% delay maintenance (FinanceBuzz 2024)
- 65% repairs preventable (Hippo Insurance 2023)
- 75% claim denials from coverage misunderstanding (This Old House)
- 37% more tasks with digital tools (Journal of Family Psychology 2023)
- Add docs/ONBOARDING_STATISTICS_SOURCES.md with full citations

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

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

iosApp/iosApp/Onboarding/OnboardingValuePropsView.swift

@@ -14,8 +14,8 @@ struct OnboardingValuePropsContent: View {
             subtitle: "Your memory just got an upgrade",
             description: "Smart reminders keep you on top of furnace filters, gutter cleaning, and everything in between. No more \"when did I last...?\" moments.",
             gradient: [Color.appPrimary, Color.appSecondary],
-            statNumber: "47%",
-            statLabel: "of homeowners forget routine maintenance"
+            statNumber: "60%",
+            statLabel: "of homeowners delay routine maintenance"
         ),
         FeatureHighlight(
             icon: "dollarsign.circle.fill",
@@ -23,8 +23,8 @@ struct OnboardingValuePropsContent: View {
             subtitle: "Prevention beats repair every time",
             description: "Catch small issues before they become expensive disasters. A $30 filter change beats a $5,000 HVAC replacement any day.",
             gradient: [Color(hex: "#34C759") ?? .green, Color(hex: "#30D158") ?? .green],
-            statNumber: "$3,000+",
-            statLabel: "average savings per year"
+            statNumber: "65%",
+            statLabel: "of repairs could have been prevented"
         ),
         FeatureHighlight(
             icon: "doc.text.fill",
@@ -32,8 +32,8 @@ struct OnboardingValuePropsContent: View {
             subtitle: "No more digging through drawers",
             description: "Snap a photo of your receipts and warranties. When something breaks, you'll know exactly what's covered—instantly.",
             gradient: [Color.appAccent, Color(hex: "#FF9500") ?? .orange],
-            statNumber: "60%",
-            statLabel: "of warranties go unused"
+            statNumber: "75%",
+            statLabel: "of claim denials from misunderstanding coverage"
         ),
         FeatureHighlight(
             icon: "person.2.fill",
@@ -41,8 +41,8 @@ struct OnboardingValuePropsContent: View {
             subtitle: "Teamwork makes the dream work",
             description: "Share your home with family members. Everyone sees what needs doing, and nobody can claim they \"didn't know.\"",
             gradient: [Color(hex: "#AF52DE") ?? .purple, Color(hex: "#BF5AF2") ?? .purple],
-            statNumber: "2x",
-            statLabel: "more tasks completed with sharing"
+            statNumber: "37%",
+            statLabel: "more tasks completed with digital tools"
         )
     ]