Merge main into family-comfort; a session state without 'started' can't crash status

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

ios/FrameControl/App/AppModel.swift

@@ -1,4 +1,5 @@
 import Citadel
+import CryptoKit
 import Foundation
 import SwiftUI
 import UIKit
@@ -33,6 +34,11 @@ final class AppModel: ObservableObject {
     }
 
     var deviceName: String { UIDevice.current.userInterfaceIdiom == .pad ? "iPad" : "iPhone" }
+    /// Stable per install: a hash of this device's SSH key, which is made once and kept in the Keychain.
+    var clientID: String {
+        let digest = SHA256.hash(data: Data(authorizedKeysLine.utf8))
+        return deviceName.lowercased() + "-" + digest.prefix(6).map { String(format: "%02x", $0) }.joined()
+    }
     private var hostKey: String? { UserDefaults.standard.string(forKey: Self.hostKeyKey) }
 
     // MARK: pairing
@@ -167,7 +173,7 @@ final class AppModel: ObservableObject {
             guard current() else { throw CancellationError() }
             step("Starting Frame Control on the headset")
             let key = Self.randomKey()
-            let server = try await HeadsetServer.start(in: dir, over: l, key: key, device: deviceName)
+            let server = try await HeadsetServer.start(in: dir, over: l, key: key, device: deviceName, client: clientID)
             guard current() else { throw CancellationError() }
             let f = try await PortForwarder.start(over: l, to: server.port)
             forwarder = f

ios/FrameControl/SSH/HeadsetServer.swift

@@ -80,8 +80,10 @@ final class HeadsetServer: @unchecked Sendable {
     }
 
     /// Starts the server in dir and waits for it to say which port it took.
-    static func start(in dir: String, over link: FrameLink, key: String, device: String) async throws -> HeadsetServer {
+    /// client is a stable id for this install (keyboard-and-trackpad pairing is kept per client).
+    static func start(in dir: String, over link: FrameLink, key: String, device: String, client: String) async throws -> HeadsetServer {
         let command = "cd \(dir) && FRAME_LOCAL=1 FRAME_UI_KEY=\(key) FRAME_DEVICE=\(shellQuote(device)) "
+            + "FRAME_CLIENT=\(shellQuote(client)) "
             + "exec python3 -I -u -B \"$PWD/ui/server.py\" --port 0 --exit-on-eof 2>&1"
         let stream = try await link.client.executeCommandStream(command)
         let box = PortWaiter()