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/Views/ConnectionChip.swift

@@ -0,0 +1,25 @@
+import SwiftUI
+
+/// Persistent connectivity indicator (UX_IOS §6). Connectivity is unambiguous: green LAN
+/// when live, amber while reconnecting, gray when the Mac is unreachable.
+struct ConnectionChip: View {
+    @EnvironmentObject var store: RemoteStore
+
+    var body: some View {
+        HStack(spacing: 6) {
+            Circle().fill(color).frame(width: 8, height: 8)
+            Text(store.connectivity.label).font(.footnote.weight(.medium))
+        }
+        .padding(.horizontal, 12).padding(.vertical, 6)
+        .background(.ultraThinMaterial, in: Capsule())
+    }
+
+    private var color: Color {
+        switch store.connectivity {
+        case .connected: .green
+        case .connecting, .reconnecting: .orange
+        case .hostOffline, .unpaired: .gray
+        case .failed: .red
+        }
+    }
+}