feat(app): add flow diagnostics and refine interface

Improve failure recovery visibility, strengthen account-session handling, and make the cross-platform interface more consistent.

OSGKeyboardExt/Typing/TypingRootView.swift

@@ -371,7 +371,9 @@ struct TypingRootView: View {
     }
 
     private var expandChevronFill: Color {
-        colorScheme == .dark ? Color(white: 0.30) : .white
+        colorScheme == .dark
+            ? OSGColor.keyboardDarkInputFill
+            : OSGColor.fixedLightContent
     }
 
     // MARK: - Editing toolbar (iPad)
@@ -423,7 +425,9 @@ struct TypingRootView: View {
     }
 
     private var editingToolbarButtonFill: Color {
-        colorScheme == .dark ? Color(white: 0.30) : .white
+        colorScheme == .dark
+            ? OSGColor.keyboardDarkInputFill
+            : OSGColor.fixedLightContent
     }
 
     /// UIKit-recycled labels — no SwiftUI Button per candidate.
@@ -773,7 +777,9 @@ struct TypingRootView: View {
     }
 
     private var selectedCandidateFill: Color {
-        colorScheme == .dark ? Color(white: 0.36) : .white
+        colorScheme == .dark
+            ? OSGColor.keyboardDarkInputFillRaised
+            : OSGColor.fixedLightContent
     }
 
     private var returnKeyFill: Color {
@@ -786,7 +792,9 @@ struct TypingRootView: View {
 
     private var returnKeyBorder: Color {
         if state.returnKeyRole.usesActionFill {
-            return Color.black.opacity(colorScheme == .dark ? 0.10 : 0.08)
+            return colorScheme == .dark
+                ? OSGColor.keyboardActionBorderDark
+                : OSGColor.keyboardActionBorderLight
         }
         return palette.divider
     }
@@ -799,7 +807,7 @@ struct TypingRootView: View {
     }
 
     private var returnKeyTextColor: Color {
-        state.returnKeyRole.usesActionFill ? .white : keyTextColor
+        state.returnKeyRole.usesActionFill ? OSGColor.fixedLightContent : keyTextColor
     }
 
     /// The send key stays recognizable in both appearances without becoming neon.

OSGKeyboardExt/Views/AIKeyboardView.swift

@@ -188,7 +188,7 @@ struct AIKeyboardView: View {
             Button(action: state.confirmPendingAIAnswer) {
                 Image(systemName: "plus")
                     .font(.system(size: 20, weight: .semibold))
-                    .foregroundStyle(.white)
+                    .foregroundStyle(OSGColor.fixedLightContent)
                     .frame(width: Layout.fieldActionWidth, height: 44)
                     .background(palette.accent, in: Capsule())
             }
@@ -709,13 +709,13 @@ struct AIKeyboardView: View {
         if state.assistantInsertionSucceeded {
             Image(systemName: "checkmark")
                 .font(.system(size: 27, weight: .bold))
-                .foregroundStyle(.white)
+                .foregroundStyle(OSGColor.fixedLightContent)
         } else {
             switch state.aiSession.phase {
             case .listening:
-                waveform(color: .white)
+                waveform(color: OSGColor.fixedLightContent)
             case .preparing, .recognizing, .generating:
-                ProgressView().tint(.white)
+                ProgressView().tint(OSGColor.fixedLightContent)
             case .inactive, .idle, .ready, .awaitingSend, .inserted, .sent, .failed:
                 ordinaryMicrophoneContent
             }
@@ -726,17 +726,17 @@ struct AIKeyboardView: View {
     private var ordinaryMicrophoneContent: some View {
         switch state.phase {
         case .recording:
-            waveform(color: Color(red: 1, green: 0.78, blue: 0.78))
+            waveform(color: OSGColor.recordingWaveform)
         case .requestingPermissions, .processing:
-            ProgressView().tint(.white)
+            ProgressView().tint(OSGColor.fixedLightContent)
         case .error:
             Image(systemName: "exclamationmark.triangle.fill")
                 .font(.system(size: 25, weight: .semibold))
-                .foregroundStyle(.white)
+                .foregroundStyle(OSGColor.fixedLightContent)
         case .idle, .denied:
             Image(systemName: "mic.fill")
                 .font(.system(size: 28, weight: .semibold))
-                .foregroundStyle(.white)
+                .foregroundStyle(OSGColor.fixedLightContent)
                 .symbolEffect(.breathe, isActive: micIsHoldingForAI)
         }
     }

OSGKeyboardExt/Views/ClipboardKeyboardViews.swift

@@ -104,7 +104,7 @@ struct ClipboardEnableGuideView: View {
                 Button(action: onOpenSettings) {
                     ExtL10n.text("keyboard.clipboard.guide.cta")
                         .font(.system(size: 15, weight: .semibold))
-                        .foregroundStyle(.white)
+                        .foregroundStyle(OSGColor.fixedLightContent)
                         .padding(.horizontal, 20)
                         .padding(.vertical, 10)
                         .background(palette.accent, in: Capsule())
@@ -222,6 +222,7 @@ struct ClipboardHistoryPanelView: View {
                 }
                 .buttonStyle(.glass)
                 .buttonBorderShape(.capsule)
+                .tint(palette.textPrimary)
 
                 Button {
                     // Dismiss the popup before publishing an empty history
@@ -231,12 +232,13 @@ struct ClipboardHistoryPanelView: View {
                 } label: {
                     ExtL10n.text("keyboard.clipboard.clear.confirm")
                         .font(.system(size: 13, weight: .semibold))
+                        .foregroundStyle(palette.background)
                         .frame(maxWidth: .infinity)
                         .frame(height: 36)
                 }
                 .buttonStyle(.glassProminent)
                 .buttonBorderShape(.capsule)
-                .tint(palette.accent)
+                .tint(palette.textPrimary)
             }
         }
         .padding(16)

OSGKeyboardExt/Views/KeyboardTopControls.swift

@@ -43,7 +43,11 @@ struct KeyboardBrandLogo: View {
                 .resizable()
                 .renderingMode(.template)
                 .scaledToFit()
-                .foregroundStyle(colorScheme == .dark ? Color.white : Color.black)
+                .foregroundStyle(
+                    colorScheme == .dark
+                        ? OSGColor.fixedLightContent
+                        : OSGColor.fixedDarkContent
+                )
                 .frame(
                     width: KeyboardTopBarMetrics.logoWidth,
                     height: KeyboardTopBarMetrics.logoHeight
@@ -222,13 +226,17 @@ struct KeyboardTopControls: View {
     }
 
     private var pressedFill: Color {
-        colorScheme == .dark ? Color(white: 0.22) : Color(white: 0.84)
+        colorScheme == .dark
+            ? OSGColor.keyboardDarkControlFill
+            : OSGColor.keyboardLightKeyPressed
     }
 
     /// 分段轨道底色与选中键面（NativeKeyboardKeyColors.fill）拉开明度；
     /// 浅色模式叠加半透明黑色，在不同宿主键盘底色上维持可见对比。
     private var tabTrackFill: Color {
-        colorScheme == .dark ? Color(white: 0.12) : Color.black.opacity(0.12)
+        colorScheme == .dark
+            ? OSGColor.keyboardDarkControlBorder
+            : OSGColor.keyboardLightControlBorder
     }
 
     private func isSelected(_ tab: KeyboardInputTab) -> Bool {

OSGKeyboardExt/Views/LastInputEditView.swift

@@ -123,7 +123,7 @@ struct LastInputEditView: View {
                     Color.clear
                     if case .listening = state.editSession {
                         Capsule()
-                            .stroke(Color.white.opacity(0.28), lineWidth: 1.5)
+                            .stroke(OSGColor.recordListeningRing, lineWidth: 1.5)
                             .scaleEffect(1 + min(max(state.level, 0), 1) * 0.08)
                             .animation(Motion.soft, value: state.level)
                     }
@@ -161,16 +161,16 @@ struct LastInputEditView: View {
     private var primaryIcon: some View {
         switch state.editSession {
         case .preparing, .processing, .applying, .appending:
-            ProgressView().tint(.white)
+            ProgressView().tint(OSGColor.fixedLightContent)
         case .review:
             Image(systemName: "checkmark")
                 .font(.system(size: 21, weight: .bold))
-                .foregroundStyle(.white)
+                .foregroundStyle(OSGColor.fixedLightContent)
         case .listening:
             WaveformView(
                 level: state.level,
                 barCount: 7,
-                color: .white,
+                color: OSGColor.fixedLightContent,
                 active: true
             )
             .frame(width: 35, height: 22)
@@ -178,7 +178,7 @@ struct LastInputEditView: View {
         default:
             Image(systemName: "mic.fill")
                 .font(.system(size: 21, weight: .semibold))
-                .foregroundStyle(.white)
+                .foregroundStyle(OSGColor.fixedLightContent)
         }
     }
 

OSGKeyboardExt/Views/NativeKeyboardKeyStyle.swift

@@ -3,32 +3,37 @@
 //
 // Shared native-like key surface used by voice and typing action rows.
 
+import OSGKeyboardShared
 import SwiftUI
 
 enum NativeKeyboardKeyColors {
     static func fill(for colorScheme: ColorScheme) -> Color {
-        colorScheme == .dark ? Color(white: 0.32) : .white
+        colorScheme == .dark
+            ? OSGColor.keyboardDarkKeyFill
+            : OSGColor.fixedLightContent
     }
 
     static func pressedFill(for colorScheme: ColorScheme) -> Color {
-        colorScheme == .dark ? Color(white: 0.23) : Color(white: 0.84)
+        colorScheme == .dark
+            ? OSGColor.keyboardDarkKeyPressed
+            : OSGColor.keyboardLightKeyPressed
     }
 
     static func text(for colorScheme: ColorScheme) -> Color {
-        colorScheme == .dark ? .white : Color(red: 0.06, green: 0.06, blue: 0.08)
+        colorScheme == .dark ? OSGColor.fixedLightContent : OSGColor.keyboardLightText
     }
 
     /// Adaptive brand green: brighter in dark mode and deeper in light mode.
     static func sendFill(for colorScheme: ColorScheme) -> Color {
         colorScheme == .dark
-            ? Color(red: 0.286, green: 0.725, blue: 0.416)
-            : Color(red: 0.196, green: 0.549, blue: 0.298)
+            ? OSGColor.keyboardDarkSend
+            : OSGColor.keyboardLightSend
     }
 
     static func sendPressedFill(for colorScheme: ColorScheme) -> Color {
         colorScheme == .dark
-            ? Color(red: 0.227, green: 0.627, blue: 0.353)
-            : Color(red: 0.157, green: 0.447, blue: 0.247)
+            ? OSGColor.keyboardDarkSendPressed
+            : OSGColor.keyboardLightSendPressed
     }
 }
 

OSGKeyboardExt/Views/ToolbarActionButtons.swift

@@ -67,7 +67,9 @@ private struct ToolbarKeySurface<Content: View>: View {
         case .standard:
             return palette.divider
         case .send:
-            return Color.black.opacity(colorScheme == .dark ? 0.10 : 0.08)
+            return colorScheme == .dark
+                ? OSGColor.keyboardActionBorderDark
+                : OSGColor.keyboardActionBorderLight
         }
     }
 }
@@ -340,7 +342,7 @@ struct RectangularToolbarButton: View {
     }
 
     private var buttonForeground: Color {
-        isSend ? .white : NativeKeyboardKeyColors.text(for: colorScheme)
+        isSend ? OSGColor.fixedLightContent : NativeKeyboardKeyColors.text(for: colorScheme)
     }
 
     // 按下即响、即震、即执行，与系统键盘 / 打字面保持一致（Button 默认松手才触发）。