iPhone and iPad app: the same features, served from the Frame

An iPhone can't run Python or ssh, but the Frame can. The app (ios/, SwiftUI)
connects with its own SSH key (Citadel), copies the server and helpers to
~/.cache/frame-control/<version> on the Frame once per version, starts
ui/server.py there with FRAME_LOCAL=1 on the Frame's 127.0.0.1, and shows the
page through an SSH tunnel. The server exits when the phone disconnects.

Server: FRAME_LOCAL=1 puts ui/local-bin on PATH, whose ssh stand-in runs each
`ssh frame COMMAND` locally (and serves as rsync's transport), so desktop and
phone share one code path. Android display goes through podman exec there, as
the Frame has no adb. FRAME_UI_KEY replaces the fixed X-Frame-UI value with a
per-session key. Power actions take the Developer Mode password via sudo -S.
--port 0 now prints the port it took.

Page: a bottom tab bar and safe areas on phones, Play buttons visible on touch
screens, saving through the share sheet, SSH/SFTP/Steam Link/remote desktop
opening in their iOS apps, and a password dialog for power.

App: pairing with the Developer Mode password once (never stored) or with a
key the user adds; host key pinned on first use; plain-language connection
errors with quiet retries; frame-control://install links; alerts and confirms.

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

ios/FrameControl/App/FrameControlApp.swift

@@ -0,0 +1,34 @@
+import SwiftUI
+
+@main
+struct FrameControlApp: App {
+    @StateObject private var model = AppModel()
+    @Environment(\.scenePhase) private var scenePhase
+
+    var body: some Scene {
+        WindowGroup {
+            RootView(model: model)
+                .task {
+                    #if DEBUG
+                    // Simulator testing without the pairing screen: print this device's key,
+                    // and connect to FRAME_TEST_HOST with it (`simctl launch` passes
+                    // SIMCTL_CHILD_FRAME_TEST_HOST through as FRAME_TEST_HOST).
+                    print("FRAME_CONTROL_KEY: \(model.authorizedKeysLine)")
+                    if model.settings == nil, let host = ProcessInfo.processInfo.environment["FRAME_TEST_HOST"] {
+                        await model.useKey(host: host, user: "steamos")
+                        return
+                    }
+                    #endif
+                    if model.settings != nil { await model.connect() }
+                }
+                .onOpenURL { url in
+                    // frame-control://install?… from a website (docs/web-install.md).
+                    guard let link = InstallLink(url.absoluteString), model.pendingInstallLinks.count < 5 else { return }
+                    model.pendingInstallLinks.append(link)
+                }
+                .onChange(of: scenePhase) { _, phase in
+                    if phase == .active { model.resume() }
+                }
+        }
+    }
+}