chore(release): bump version to 2.1.6 (build 131)

Version: CURRENT_PROJECT_VERSION 130 -> 131 (project.yml, AGENTS.md, READMEs,
docs/llms.txt).

fix(flow): host-app identification now compiles in every build configuration
(Debug, TestFlight, Release). The arbiter probe and HostAppIdentity were
DEBUG-only, so TestFlight/App Store builds never knew the host bundle id and
could not auto-return after a startflow handoff. Debug-only logging and the
Home test card are unchanged.

Also includes the pending work in the tree:
- Home: single account/setup card surface (HomeAccountSurfacePolicy/Views)
- Wide screens: voice key row and centred mic placement, iPhone Duo layout
- Keyboard: clipboard skill ranking and AI skill layout updates
- Debug: account session handoff to the Simulator (+ import script)
- Docs: portfolio assets, privacy policy URL, site/README refresh

OSGKeyboardShared/Typing/VoiceKeyRowLayout.swift

@@ -0,0 +1,84 @@
+// VoiceKeyRowLayout.swift
+// OSGKeyboard · Shared
+//
+// Keyboard-style voice bottom row for wide hosts (iPad, unfolded iPhone Duo).
+
+import CoreGraphics
+
+/// Horizontal geometry of the wide-host voice bottom row:
+///
+///     [leadingSide][leadingContext][    send    ][trailingContext][trailingSide]
+///
+/// - The four icon keys (space / undo / edit / delete) share one width and send
+///   is exactly twice as wide, so the primary action reads as the main key while
+///   the row fills edge to edge with uniform gaps. The row is symmetric, so send
+///   sits on the centre line under the microphone.
+/// - No globe: the voice surface leaves input-mode switching to the typing tab.
+/// - Context slots (undo / edit) exist even while the keys are disabled, so
+///   nothing in the row shifts when they toggle.
+///
+/// Coordinates are relative to the row's own leading edge.
+public struct VoiceKeyRowLayout: Equatable, Sendable {
+    public struct Slot: Equatable, Sendable {
+        public let minX: CGFloat
+        public let width: CGFloat
+
+        public var midX: CGFloat { minX + width / 2 }
+        public var maxX: CGFloat { minX + width }
+
+        public init(minX: CGFloat, width: CGFloat) {
+            self.minX = minX
+            self.width = width
+        }
+    }
+
+    /// Send width as a multiple of one icon key.
+    public static let sendWidthMultiplier: CGFloat = 2
+    /// Below this host width the icon keys would shrink past a comfortable
+    /// touch target, so narrower hosts keep the phone's circle cluster.
+    public static let minimumHostWidth: CGFloat = 500
+
+    public let leadingSide: Slot
+    public let leadingContext: Slot
+    public let send: Slot
+    public let trailingContext: Slot
+    public let trailingSide: Slot
+
+    /// Wide hosts only: iPad-scale metrics, the expanded-phone tier, or a
+    /// landscape iPhone (whose shorter panel has no room for two circle rows),
+    /// with enough width for the row. Portrait iPhones keep the circle
+    /// cluster, which suits one-handed thumb reach.
+    public static func isAvailable(
+        usesIPadMetrics: Bool,
+        usesExpandedPhoneMetrics: Bool,
+        usesCompactHeightPhoneMetrics: Bool,
+        hostWidth: CGFloat
+    ) -> Bool {
+        (usesIPadMetrics || usesExpandedPhoneMetrics || usesCompactHeightPhoneMetrics)
+            && hostWidth >= minimumHostWidth
+    }
+
+    /// - Parameter rowWidth: The row's width, i.e. the same width the typing bottom row spans.
+    public static func make(rowWidth: CGFloat) -> VoiceKeyRowLayout {
+        let spacing = KeyboardChromeLayout.actionKeySpacing
+
+        // 4 icon keys + one send key worth `sendWidthMultiplier` icon keys,
+        // with 4 gaps between those five.
+        let keySpan = max(0, rowWidth - spacing * 4)
+        let keyWidth = keySpan / (4 + sendWidthMultiplier)
+
+        let leadingSide = Slot(minX: 0, width: keyWidth)
+        let leadingContext = Slot(minX: leadingSide.maxX + spacing, width: keyWidth)
+        let send = Slot(minX: leadingContext.maxX + spacing, width: keyWidth * sendWidthMultiplier)
+        let trailingContext = Slot(minX: send.maxX + spacing, width: keyWidth)
+        let trailingSide = Slot(minX: trailingContext.maxX + spacing, width: keyWidth)
+
+        return VoiceKeyRowLayout(
+            leadingSide: leadingSide,
+            leadingContext: leadingContext,
+            send: send,
+            trailingContext: trailingContext,
+            trailingSide: trailingSide
+        )
+    }
+}

OSGKeyboardShared/Typing/VoiceMicPlacement.swift

@@ -0,0 +1,29 @@
+// VoiceMicPlacement.swift
+// OSGKeyboard · Shared
+//
+// Vertical placement of the voice surface's mic row. Every shell height
+// (phone, unfolded Duo, landscape, iPad narrow / wide) leaves a different
+// amount of free height between the top bar and the bottom row; this splits it
+// into the context slot above the mic and the gap below it with one rule, so
+// the mic sits centred in the area below the top bar on every device.
+
+import CoreGraphics
+
+public enum VoiceMicPlacement {
+    /// Never let the mic touch the bottom row.
+    public static let minimumGap: CGFloat = 10
+
+    /// Context slot height for a free height (`contextAndGap` = slot + gap).
+    /// Centred means the slot above the mic equals the gap plus the bottom row
+    /// below it, but the slot never drops under `minimumContextHeight` (the
+    /// live transcript) and the gap never under `minimumGap`.
+    public static func contextHeight(
+        contextAndGap: CGFloat,
+        bottomRowHeight: CGFloat,
+        minimumContextHeight: CGFloat
+    ) -> CGFloat {
+        let centred = (contextAndGap + bottomRowHeight) / 2
+        let ceiling = max(0, contextAndGap - minimumGap)
+        return min(ceiling, max(minimumContextHeight, centred))
+    }
+}