feat(ui-refactor 3/4): 聊天消息进场 fade-up（原版强缓动）；审批卡/Composer/ToolChips 经 token 切换自动对齐原版规格

apps/desktop/src/renderer/src/components/MessageItem.tsx

@@ -395,7 +395,10 @@ function AssistantTurnBase({
   if (answerText.trim() && !hasAnswer) setHasAnswer(true)
 
   return (
-    <div className="min-w-0 max-w-full">
+    <div
+      className="min-w-0 max-w-full"
+      style={{ animation: 'fade-up 400ms cubic-bezier(0.23, 1, 0.32, 1) both' }}
+    >
       {hasProcess && (
         <div className="border-b border-line pb-1">
           <button
@@ -651,7 +654,11 @@ function MessageItemBase({
 
   if (message.role === 'assistant') {
     return (
-      <div ref={ref} className="min-w-0 max-w-full">
+      <div
+        ref={ref}
+        className="min-w-0 max-w-full"
+        style={{ animation: 'fade-up 400ms cubic-bezier(0.23, 1, 0.32, 1) both' }}
+      >
         <AssistantTurn
           messages={[message]}
           tools={tools}