feat(mobile): tablet layout pass and foldable-ready size class (#2569)

The tablet ran the phone layout with a half-finished iPad draft on top: two
custom sidebars, a leftover overflow menu, split Files/Changes header buttons,
and phone-width sheets stretched across a 13" screen. This brings it onto the
phone's navigation model and keeps only the differences a large screen earns.

- Sessions are a persistent resizable left sidebar; the overflow menu is gone
  and its destinations moved into that sidebar's footer (connected instance,
  settings, pending web update) and into the workspace drawer.
- The workspace (Changes / Files / Terminal / Notes / MCP) is the phone's
  drawer everywhere: a resizable right sidebar where the screen can host one
  (up to 900px) and the full-cover drawer otherwise, with its mounted panes —
  an open diff, an edited file, an attached terminal — surviving rotation.
- Header dropdowns are anchored popovers: the recents switcher mirrors the
  usage overlay on the left, and its trigger is sized to the title rather than
  to the free width.
- App-level pages (settings, instances, update, an opened plan) render as
  centered dialogs instead of covering the screen.
- Overlays center on the chat column through published insets, so the model
  and directory pickers no longer sit off-centre; the directory picker also
  stops overriding the shared width clamp.
- Wide chat layout applies to mobile surfaces, where a tablet chat column is
  finally wide enough for the setting to mean anything.

The layout gate is a live size class rather than a device check, so Android
tablets and foldables are covered by the same code:

- `enabled` when the shortest viewport side is at le
  sw600dp). The short side is what makes this a size question instead of a
  device question — a phone reports ~360-430 whichev
  unfolded book foldable ~600+, and folding shut drops back under it. iPads
  also answer on identity, since iPadOS hands out od
- `roomyForPanels` when landscape and at least 1000px wide, which is what it
  takes to host the sidebar, the panel and a readabl
  foldables miss it in BOTH orientations — their long side is barely wider
  than a tablet's short one — so they keep the portr

Every consumer re-decides instead of remembering wha
open sidebar closes if the device folds shut under it. iPad behaviour is
unchanged: its landscape widths all clear the panel
ones do not, exactly as the previous orientation check did.

Hardware keyboards are read natively. iOS reports them through GCKeyboard,
published to the web layer at document start and kep
disconnect and foregrounding; the layer stops inferring once that answers. A
single early publish was not enough — the connect no
already-attached keyboard fires before the page exists, and GameController can
populate late — so the state is re-published across
resume. With a keyboard attached the draft screen keeps its starter chips and
the composer never collapses; tablets skip the colla
Runtimes with no native answer fall back to inferring it from the keyboard
bridge, and only ever conclude "hardware" from silen

Also: sidebar rows no longer sit on a differently ti
footer is no longer clipped by an over-tall content box, the resize handles
moved above the panes' own overlays so they can actu
now-unreachable overflow menu, fullscreen terminal/MCP/notes surfaces and their
locale key are deleted.

Device behaviour is unverified — the tablet layout,
keyboard bridge and the foldable size class have not been exercised on
hardware, and the 600/1000 thresholds are derived fr
rather than measured on a foldable.

packages/mobile/ios/App/App/AppDelegate.swift

@@ -1,5 +1,6 @@
 import UIKit
 import Capacitor
+import GameController
 import UserNotifications
 import WebKit
 import WidgetKit
@@ -78,22 +79,91 @@ let apnsEnvironment: String = {
     return profile.range(of: pattern, options: .regularExpression) != nil ? "development" : "production"
 }()
 
-/// Bridge subclass (referenced from Main.storyboard) whose only job is to expose the APNs
-/// environment as a document-start user script. This runs before any page JS, so token
-/// registration (useNativePushRegistration) always sees it — injecting later from the scene
-/// lifecycle raced the registration call and lost on first launch.
+/// Bridge subclass (referenced from Main.storyboard) whose job is to expose native-only
+/// facts to the web layer as document-start user scripts. These run before any page JS,
+/// so consumers always see them — injecting later from the scene lifecycle raced the
+/// consumer (push registration) and lost on first launch.
 ///
-/// The script must be added in capacitorDidLoad(), NOT webViewConfiguration(for:): Capacitor's
+/// The scripts must be added in capacitorDidLoad(), NOT webViewConfiguration(for:): Capacitor's
 /// prepareWebView replaces the configuration's userContentController with its own right after
 /// calling webViewConfiguration(for:), which silently discards any user script added there.
 /// capacitorDidLoad() runs after that swap but before loadWebView() starts the initial page load.
 class BridgeViewController: CAPBridgeViewController {
+    private var keyboardObservers: [NSObjectProtocol] = []
+
     override func capacitorDidLoad() {
         super.capacitorDidLoad()
-        let source = "window.__OPENCHAMBER_APNS_ENV__ = '\(apnsEnvironment)';"
+        // GCKeyboard is the only authoritative answer to "is a hardware keyboard
+        // attached?". The web layer can otherwise only INFER it from a keyboard
+        // that never appears, which costs the user one focus before the layout
+        // settles — so the state is stamped at document start and kept live.
+        //
+        // At this point GameController has usually NOT finished discovery yet, so
+        // an already-attached keyboard still reads as nil here. The stamp is only
+        // the optimistic first answer; refreshHardwareKeyboardState() below is
+        // what actually settles it once the page exists.
+        let attached = GCKeyboard.coalesced != nil
+        let source = """
+        window.__OPENCHAMBER_APNS_ENV__ = '\(apnsEnvironment)';
+        window.__OPENCHAMBER_HARDWARE_KEYBOARD__ = \(attached ? "true" : "false");
+        """
         webView?.configuration.userContentController.addUserScript(
             WKUserScript(source: source, injectionTime: .atDocumentStart, forMainFrameOnly: true)
         )
+        observeHardwareKeyboard()
+    }
+
+    override func viewDidAppear(_ animated: Bool) {
+        super.viewDidAppear(animated)
+        // Two races make a single early publish unreliable for a keyboard that was
+        // ALREADY attached at launch, which is why it only ever worked when the
+        // user plugged one in afterwards:
+        //  - GCKeyboardDidConnect for a pre-attached keyboard fires during launch,
+        //    before the web page exists, so its evaluateJavaScript lands in a
+        //    context the page load then throws away;
+        //  - GameController can populate `coalesced` a beat after launch anyway.
+        // Re-publishing across the first seconds covers both; the web side adopts
+        // idempotently, so repeats are free.
+        refreshHardwareKeyboardState()
+        for delay in [0.3, 1.0, 2.5] {
+            DispatchQueue.main.asyncAfter(deadline: .now() + delay) { [weak self] in
+                self?.refreshHardwareKeyboardState()
+            }
+        }
+    }
+
+    /// Re-read GameController and push the current answer to the web layer.
+    /// Also called when the app returns to the foreground — a keyboard can be
+    /// attached or detached while backgrounded, with no notification delivered.
+    func refreshHardwareKeyboardState() {
+        publishHardwareKeyboardState(GCKeyboard.coalesced != nil)
+    }
+
+    private func observeHardwareKeyboard() {
+        let center = NotificationCenter.default
+        keyboardObservers = [
+            center.addObserver(forName: .GCKeyboardDidConnect, object: nil, queue: .main) { [weak self] _ in
+                self?.publishHardwareKeyboardState(true)
+            },
+            center.addObserver(forName: .GCKeyboardDidDisconnect, object: nil, queue: .main) { [weak self] _ in
+                // A second keyboard may still be attached (Stage Manager, dock swaps).
+                self?.publishHardwareKeyboardState(GCKeyboard.coalesced != nil)
+            },
+        ]
+    }
+
+    private func publishHardwareKeyboardState(_ attached: Bool) {
+        let value = attached ? "true" : "false"
+        webView?.evaluateJavaScript("""
+        window.__OPENCHAMBER_HARDWARE_KEYBOARD__ = \(value);
+        window.dispatchEvent(new CustomEvent('oc:hardware-keyboard', { detail: { attached: \(value) } }));
+        """)
+    }
+
+    deinit {
+        for observer in keyboardObservers {
+            NotificationCenter.default.removeObserver(observer)
+        }
     }
 }
 
@@ -137,6 +207,10 @@ class SceneDelegate: UIResponder, UIWindowSceneDelegate {
             UIApplication.shared.applicationIconBadgeNumber = 0
         }
 
+        // A keyboard can be attached or detached while the app is backgrounded,
+        // with no GameController notification delivered to it.
+        (window?.rootViewController as? BridgeViewController)?.refreshHardwareKeyboardState()
+
         // Refresh the widgets' session overview now that the WebView is loaded and state is fresh.
         writeWidgetSnapshot()
     }