feat(v1.9.0): add domain availability lookup and watchlist foundation

- implement availability detection (available/registered/unknown)
- integrate availability into domain results
- add lightweight domain suggestions
- introduce local watchlist with persistence
- add WatchlistView and toolbar access
- include availability in export

1 files changed, 69 insertions, 0 deletions

diff --git a/DomainDig/WatchlistView.swift b/DomainDig/WatchlistView.swift
new file mode 100644
index 0000000..c44fc65
--- /dev/null
+++ b/DomainDig/WatchlistView.swift
@@ -0,0 +1,69 @@
+import SwiftUI
+
+struct WatchlistView: View {
+    @Bindable var viewModel: DomainViewModel
+    @Environment(\.dismiss) private var dismiss
+
+    var body: some View {
+        List {
+            if viewModel.watchedDomains.isEmpty {
+                Text("No watched domains")
+                    .font(.system(.callout, design: .monospaced))
+                    .foregroundStyle(.secondary)
+                    .listRowBackground(Color(.systemGray6).opacity(0.5))
+            } else {
+                ForEach(viewModel.watchedDomains) { watchedDomain in
+                    Button {
+                        viewModel.domain = watchedDomain.domain
+                        dismiss()
+                        viewModel.run()
+                    } label: {
+                        VStack(alignment: .leading, spacing: 4) {
+                            Text(watchedDomain.domain)
+                                .font(.system(.callout, design: .monospaced))
+                                .foregroundStyle(.primary)
+                            Text(statusLabel(watchedDomain.lastKnownAvailability))
+                                .font(.system(.caption2, design: .monospaced))
+                                .foregroundStyle(statusColor(watchedDomain.lastKnownAvailability))
+                        }
+                    }
+                    .listRowBackground(Color(.systemGray6).opacity(0.5))
+                }
+                .onDelete { offsets in
+                    viewModel.removeWatchedDomains(at: offsets)
+                }
+            }
+        }
+        .scrollContentBackground(.hidden)
+        .background(Color.black)
+        .navigationTitle("Watchlist")
+        .toolbar {
+            if !viewModel.watchedDomains.isEmpty {
+                EditButton()
+            }
+        }
+        .preferredColorScheme(.dark)
+    }
+
+    private func statusLabel(_ status: DomainAvailabilityStatus?) -> String {
+        switch status {
+        case .available:
+            return "Available"
+        case .registered:
+            return "Registered"
+        case .unknown, .none:
+            return "Unknown"
+        }
+    }
+
+    private func statusColor(_ status: DomainAvailabilityStatus?) -> Color {
+        switch status {
+        case .available:
+            return .green
+        case .registered:
+            return .yellow
+        case .unknown, .none:
+            return .secondary
+        }
+    }
+}