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/Typing/KeyboardSurfaceRoot.swift

@@ -8,6 +8,7 @@ import OSGKeyboardShared
 
 struct KeyboardSurfaceRoot: View {
     @Environment(\.colorScheme) private var colorScheme
+    @Namespace private var keyboardTabSelectionNamespace
 
     @ObservedObject var state: KeyboardState
     @ObservedObject var typing: TypingSessionController
@@ -68,6 +69,16 @@ struct KeyboardSurfaceRoot: View {
         // Overlays are siblings of the surfaces, so the palette has to be
         // injected here or they fall back to the environment's dark default.
         .environment(\.themePalette, palette)
+        // The input surfaces are replaced when switching tabs. Keep one
+        // namespace above that switch so the selected glass pill can morph
+        // between the outgoing and incoming top-control instances.
+        .environment(\.keyboardTabSelectionNamespace, keyboardTabSelectionNamespace)
+        // Bottom-anchored on purpose: UIKit hands the input view a container up
+        // to the full screen height while the keyboard slides in, and centering
+        // a fixed-height surface in it parks the whole keyboard above the
+        // visible slot — which reads as a blank keyboard whenever that frame
+        // lingers (a slow Universal Clipboard read, a system alert).
+        .frame(maxWidth: .infinity, maxHeight: .infinity, alignment: .bottom)
         .animation(.easeInOut(duration: 0.15), value: state.surface)
         .onChange(of: state.surface) { _, newSurface in
             if newSurface != .typing {
@@ -90,26 +101,30 @@ struct KeyboardSurfaceRoot: View {
 
     @ViewBuilder
     private var clipboardOverlayLayer: some View {
-        switch state.clipboardOverlay {
-        case .none:
+        if !state.canShowClipboardEntry {
             EmptyView()
-        case .enableGuide:
-            ClipboardEnableGuideView(
-                onClose: state.dismissClipboardOverlay,
-                onOpenSettings: {
-                    state.dismissClipboardOverlay()
-                    state.openClipboardSettings()
-                }
-            )
-        case .historyPanel:
-            ClipboardHistoryPanelView(
-                history: ClipboardHistoryStore.shared,
-                onClose: state.dismissClipboardOverlay,
-                onClear: state.clearClipboardHistory,
-                onInsert: { state.insertClipboardText($0) },
-                onDelete: { state.deleteClipboardHistoryEntry($0) },
-                pastePermissionHint: nil
-            )
+        } else {
+            switch state.clipboardOverlay {
+            case .none:
+                EmptyView()
+            case .enableGuide:
+                ClipboardEnableGuideView(
+                    onClose: state.dismissClipboardOverlay,
+                    onOpenSettings: {
+                        state.dismissClipboardOverlay()
+                        state.openClipboardSettings()
+                    }
+                )
+            case .historyPanel:
+                ClipboardHistoryPanelView(
+                    history: ClipboardHistoryStore.shared,
+                    onClose: state.dismissClipboardOverlay,
+                    onClear: state.clearClipboardHistory,
+                    onInsert: { state.insertClipboardText($0) },
+                    onDelete: { state.deleteClipboardHistoryEntry($0) },
+                    pastePermissionHint: nil
+                )
+            }
         }
     }
 }

OSGKeyboardExt/Typing/TypingRootView.swift

@@ -122,7 +122,9 @@ struct TypingRootView: View {
         if hasCandidateContent {
             // Composing Chinese/English candidates hide the clipboard strip.
             candidateBar
-        } else if let suggestion = state.clipboardSuggestionText, !suggestion.isEmpty {
+        } else if state.canShowClipboardEntry,
+                  let suggestion = state.clipboardSuggestionText,
+                  !suggestion.isEmpty {
             // Same slot as logo + capsule tabs — hide chrome until dismissed.
             ClipboardSuggestionBar(
                 text: suggestion,
@@ -548,6 +550,7 @@ struct TypingRootView: View {
             )
             .fill(visualKeyFill(for: key, pressed: showPressed))
         )
+        // 无投影：与 NativeKeyboardKeySurface 一致，靠填充 + 描边表达层次。
         .overlay(
             RoundedRectangle(
                 cornerRadius: TypingLayoutMetrics.keyCornerRadius,
@@ -555,11 +558,6 @@ struct TypingRootView: View {
             )
             .stroke(visualKeyBorder(for: key), lineWidth: 0.5)
         )
-        .shadow(
-            color: Color.black.opacity(showPressed ? 0.04 : 0.13),
-            radius: showPressed ? 0.5 : 1,
-            y: showPressed ? 0 : 1
-        )
         .scaleEffect(pressed ? 0.98 : 1)
         .animation(.easeOut(duration: 0.08), value: pressed)
         .accessibilityElement()