nvrsion: Add fix for QR Code Scan Failure in AppStore, Sync, and Tests; explore connection failures over local network; update Info.plist, Models, and SettingsView.

Nucleic-Promote: 1
Co-authored-by: Nucleic <[email protected]>

NucleicRemote/NucleicRemote/Info.plist

@@ -6,6 +6,13 @@
 	<array>
 		<string>_nucleic._tcp</string>
 	</array>
+	<!-- iOS 14+ gates ALL local-network access — both Bonjour discovery (_nucleic._tcp above)
+	     and a direct NWConnection to the Mac's LAN IP from the pairing QR — behind the
+	     local-network permission, which only prompts if this usage string is present. Without
+	     it the grant never happens and every LAN connection fails silently, so pairing and
+	     reconnect appear to "do nothing." -->
+	<key>NSLocalNetworkUsageDescription</key>
+	<string>Nucleic connects to your Mac on the local network to pair and to sync your sessions and approvals.</string>
 	<key>NucleicChannel</key>
 	<string>$(NUCLEIC_CHANNEL)</string>
 	<!-- The short git commit this build came from, shown in the non-release banner to match

NucleicRemote/NucleicRemote/Models/RemoteStore.swift

@@ -695,7 +695,35 @@ final class RemoteStore: ObservableObject {
     }
 
     private func makeChannel(_ endpoint: NWEndpoint) -> NWFrameChannel {
-        NWFrameChannel(endpoint: endpoint)
+        let channel = NWFrameChannel(endpoint: endpoint)
+        // Surface a transport-level failure with an actionable message. Without this, a refused
+        // connection or a denied local-network permission finished the frame stream and only
+        // showed up as a generic "handshake closed" — hiding the real (usually fixable) cause.
+        channel.onFailed = { [weak self] error in
+            Task { @MainActor in self?.handleTransportFailure(error) }
+        }
+        return channel
+    }
+
+    /// Map an `NWConnection` failure to a connectivity state the pairing/onboarding UI can act on.
+    /// Only meaningful while we're still establishing the link; once `.connected`, a drop is the
+    /// normal `.closed` → reconnect path's job.
+    private func handleTransportFailure(_ error: String) {
+        guard connectivity != .connected else { return }
+        connectivity = .failed(Self.friendlyTransportError(error))
+    }
+
+    /// Turn a raw `NWError` string into a short, fixable hint. The common onboarding failures are
+    /// a denied Local Network permission (EPERM / -65555) and the Mac not listening (refused).
+    private static func friendlyTransportError(_ error: String) -> String {
+        let lower = error.lowercased()
+        if lower.contains("denied") || lower.contains("not permitted") || lower.contains("65555") {
+            return "Can't reach the local network. In Settings ▸ Nucleic, allow Local Network access, then try again."
+        }
+        if lower.contains("refused") {
+            return "Your Mac refused the connection. Check that remote access is still on in Nucleic ▸ Settings."
+        }
+        return "Couldn't connect to your Mac — make sure it's on the same Wi‑Fi and remote access is on."
     }
 
     private func resolveEndpoint(fingerprint: String?, lanHost: String?, lanPort: UInt16?) -> NWEndpoint? {

NucleicRemote/NucleicRemote/Views/SettingsView.swift

@@ -126,6 +126,10 @@ struct PairingIntroView: View {
             }
             .buttonStyle(.borderedProminent)
 
+            // Feedback after a scan: the whole UI is still the intro until pairing completes, so
+            // without this a failed or in-flight pair looks like "nothing happened."
+            pairingStatus
+
             VStack(spacing: 6) {
                 Button { store.enterDemo() } label: {
                     Label("Explore a demo — no Mac needed", systemImage: "play.circle")
@@ -151,4 +155,26 @@ struct PairingIntroView: View {
             }
         }
     }
+
+    /// A status line reflecting an in-flight or failed pairing attempt. Silent in the resting
+    /// `.unpaired` state (the intro copy already covers that).
+    @ViewBuilder
+    private var pairingStatus: some View {
+        switch store.connectivity {
+        case .connecting, .reconnecting:
+            Label("Connecting to your Mac…", systemImage: "arrow.triangle.2.circlepath")
+                .font(.footnote).foregroundStyle(.secondary)
+        case .hostOffline:
+            Label("Can't reach your Mac. Make sure it's on the same Wi‑Fi and remote access is on.",
+                  systemImage: "wifi.exclamationmark")
+                .font(.footnote).foregroundStyle(.orange)
+                .multilineTextAlignment(.center).padding(.horizontal, 32)
+        case .failed(let message):
+            Label(message, systemImage: "exclamationmark.triangle.fill")
+                .font(.footnote).foregroundStyle(.red)
+                .multilineTextAlignment(.center).padding(.horizontal, 32)
+        case .connected, .unpaired:
+            EmptyView()
+        }
+    }
 }