Phase 0: scaffold

Two SPM packages (VNCCore, VNCUI) + thin iOS app target wired via
xcodegen. Builds for iPhone 17 simulator, unit tests pass.

- VNCCore: SessionState, SessionController stub, Transport protocol
  with DirectTransport (NWConnection), DiscoveryService (Bonjour on
  _rfb._tcp and _workstation._tcp), SavedConnection @Model,
  ConnectionStore, KeychainService, ClipboardBridge
- VNCUI: ConnectionListView, AddConnectionView, SessionView,
  FramebufferView/FramebufferUIView (UIKit CALayer), InputMapper,
  SettingsView; UIKit bits guarded with #if canImport(UIKit) so
  swift test runs on macOS
- App: @main VNCApp, AppStateController state machine, RootView
- RoyalVNCKit dependency pinned to main (transitive CryptoSwift
  constraint blocks tagged releases)
- xcodegen Project.yml + README + .gitignore

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

.gitignore

@@ -0,0 +1,21 @@
+# Xcode
+*.xcodeproj/xcuserdata/
+*.xcodeproj/project.xcworkspace/xcuserdata/
+*.xcworkspace/xcuserdata/
+DerivedData/
+*.xcuserstate
+
+# Swift Package Manager
+.build/
+.swiftpm/
+Package.resolved
+
+# macOS
+.DS_Store
+
+# Claude Code local settings
+.claude/settings.local.json
+
+# xcodegen output
+# (keep the .xcodeproj out of git; regenerate from Project.yml)
+Screens.xcodeproj/