Keep the page clear of iOS safe areas everywhere; research typing, pointing and mirroring into the Frame

- Header, content, tab bar, status strip, drawer and toasts add the notch,
  Dynamic Island, rounded-corner and home-indicator insets on every side
  (zero on desktops). Phones on their side use the bottom tab bar layout.
- The phone tab bar hides while a text field has focus, instead of riding
  on the keyboard.
- DEBUG hook FRAME_TEST_LANDSCAPE for checking this in the Simulator.
- docs/streaming.md: iPhone mirroring (UxPlay, broadcast extension) and
  keyboard/mouse input (uinput needs no sudo on the Frame, verified).

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

ios/FrameControl/App/FrameControlApp.swift

@@ -14,6 +14,11 @@ struct FrameControlApp: App {
                     // 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)")
+                    // FRAME_TEST_LANDSCAPE=1 turns the app on its side, to check the safe areas there.
+                    if ProcessInfo.processInfo.environment["FRAME_TEST_LANDSCAPE"] != nil,
+                       let scene = UIApplication.shared.connectedScenes.first as? UIWindowScene {
+                        scene.requestGeometryUpdate(.iOS(interfaceOrientations: .landscapeRight))
+                    }
                     // FRAME_TEST_PAIR="host|user|password" runs the real password pairing.
                     if model.settings == nil, let pair = ProcessInfo.processInfo.environment["FRAME_TEST_PAIR"] {
                         let f = pair.components(separatedBy: "|")