M4: NucleicRemote iPhone app — SwiftUI client over the shared protocol

A real iOS Xcode app (ios/NucleicRemote) linking the NucleicProtocol SwiftPM
library as a local package. Builds for the iOS 27 simulator and launches to the
pairing screen.

- Transport: NWFrameChannel (NWConnection) + LANDiscovery (Bonjour _nucleic._tcp).
- Engine: drives NucleicProtocol.SyncClient (Noise XXpsk0 pair / IK reconnect,
  hello/welcome, HostMsg→Event stream).
- State: RemoteStore (ObservableObject) — the single on-device projection of host
  state; IdentityStore persists the device identity (Keychain) + pinned host.
- UI (UX_IOS): attention-first SessionsView, SessionDetailView (transcript/diff +
  status-driven action area / composer), ApprovalCardView with Face ID gate on
  high-risk approvals + allow-always menu, PairingScannerView (AVFoundation QR),
  SettingsView, connection chip. Same status glyphs/semantics as the Mac.

Add-iPhone QR display + server start live on the macOS side (follow-up); push /
Live Activity are M5 (needs the relay). gitignore keeps this .xcodeproj despite
the blanket *.xcodeproj rule.

Co-Authored-By: Claude Opus 4.8 (1M context) <[email protected]>

NucleicRemote/NucleicRemote/NucleicRemoteApp.swift

@@ -0,0 +1,32 @@
+import SwiftUI
+
+@main
+struct NucleicRemoteApp: App {
+    @StateObject private var store = RemoteStore()
+
+    var body: some Scene {
+        WindowGroup {
+            RootView()
+                .environmentObject(store)
+                .onAppear { store.onAppear() }
+        }
+    }
+}
+
+struct RootView: View {
+    @EnvironmentObject var store: RemoteStore
+
+    var body: some View {
+        if store.isPaired {
+            TabView {
+                SessionsView()
+                    .tabItem { Label("Sessions", systemImage: "square.stack.3d.up") }
+                    .badge(store.needsYouCount)
+                SettingsView()
+                    .tabItem { Label("Settings", systemImage: "gearshape") }
+            }
+        } else {
+            PairingIntroView()
+        }
+    }
+}