feat(keyboard): ship AI hint carousel, home library cards, and clipboard polish

Rotate AI idle suggestions with optional remote packs, move history/dictionary onto self-sizing Home preview cards, harden clipboard capture/prompting, and simplify keyboard chrome by dropping most liquid-glass shadows.

OSGKeyboardExt/Services/EditHintScheduler.swift

@@ -0,0 +1,71 @@
+// EditHintScheduler.swift
+// OSGKeyboard · Keyboard Extension
+//
+// Owns the edit-hint lifetime so every producer shares one expiration order.
+
+import Foundation
+import OSGKeyboardShared
+
+@MainActor
+final class EditHintScheduler {
+    typealias Sleeper = @MainActor (Duration) async -> Void
+
+    private let state: KeyboardState
+    private let sleeper: Sleeper
+    private var task: Task<Void, Never>?
+    private var generation: UInt64 = 0
+
+    init(
+        state: KeyboardState,
+        sleeper: @escaping Sleeper = { duration in
+            try? await Task.sleep(for: duration)
+        }
+    ) {
+        self.state = state
+        self.sleeper = sleeper
+    }
+
+    func show(message: String, isPositive: Bool, duration: Duration) {
+        let scheduledGeneration = advanceGeneration()
+        task?.cancel()
+
+        state.editHint = message
+        state.editHintIsPositive = isPositive
+
+        let sleeper = sleeper
+        task = Task { @MainActor [weak self, sleeper] in
+            await sleeper(duration)
+            guard let self, self.generation == scheduledGeneration else {
+                return
+            }
+            self.task = nil
+            self.clearHint()
+        }
+    }
+
+    func clearPositive() {
+        guard state.editHintIsPositive else { return }
+        advanceGeneration()
+        task?.cancel()
+        task = nil
+        clearHint()
+    }
+
+    func invalidate() {
+        advanceGeneration()
+        task?.cancel()
+        task = nil
+        clearHint()
+    }
+
+    @discardableResult
+    private func advanceGeneration() -> UInt64 {
+        generation &+= 1
+        return generation
+    }
+
+    private func clearHint() {
+        state.editHint = nil
+        state.editHintIsPositive = false
+    }
+}