feat(v3.2.0): add Data+ tier and external data integrations

- introduce Data+ tier for advanced data features
- add ownership history and DNS history
- expand subdomain discovery with external sources
- add domain pricing insights
- implement local usage/credit system
- integrate external data service layer with rate limiting
- extend export and CLI for Data+ features

1 files changed, 12 insertions, 1 deletions

diff --git a/DomainDig/PaywallView.swift b/DomainDig/PaywallView.swift
index a21448f..d0293a8 100644
--- a/DomainDig/PaywallView.swift
+++ b/DomainDig/PaywallView.swift
@@ -10,7 +10,7 @@ struct PaywallView: View {
         NavigationStack {
             List {
                 Section {
-                    Text("Pro unlocks automation, larger runs, and export convenience while keeping the core lookup experience free.")
+                    Text("Pro unlocks workflows, scale, and exports. Data+ adds deeper external intelligence with local-first usage credits and no account requirement.")
                         .font(appDensity.font(.body, design: .default))
                         .foregroundStyle(.secondary)
                         .fixedSize(horizontal: false, vertical: true)
@@ -23,6 +23,13 @@ struct PaywallView: View {
                     featureRow("Advanced exports")
                 }
 
+                Section("What Data+ Unlocks") {
+                    featureRow("Ownership history")
+                    featureRow("DNS history")
+                    featureRow("Extended subdomains")
+                    featureRow("External pricing signals")
+                }
+
                 Section("Subscription") {
                     if purchaseService.isLoadingProducts {
                         ProgressView("Loading pricing…")
@@ -116,6 +123,10 @@ struct PaywallView: View {
             return "Pro Monthly"
         case PurchaseService.yearlyProductID:
             return "Pro Yearly"
+        case PurchaseService.dataPlusMonthlyProductID:
+            return "Data+ Monthly"
+        case PurchaseService.dataPlusYearlyProductID:
+            return "Data+ Yearly"
         default:
             return product.displayName
         }