fix: restore polished account experience and align AI with Lark design

frontend/src/ai/ChatPanel.tsx

@@ -188,7 +188,12 @@ export function ChatPanel({
   useEffect(() => {
     if (!open) return;
     previousFocus.current = document.activeElement as HTMLElement;
-    input.current?.querySelector("textarea")?.focus();
+    const textarea = input.current?.querySelector("textarea");
+    if (textarea && !textarea.disabled) textarea.focus();
+    else
+      root.current
+        ?.querySelector<HTMLButtonElement>('button[aria-label="收起研究助手"]')
+        ?.focus();
     return () => {
       requestAnimationFrame(() => {
         if (
@@ -265,6 +270,7 @@ export function ChatPanel({
       ref={root}
       hidden={!open}
       className="ai-chat"
+      id="research-assistant"
       aria-label="AI 研究助手"
       onKeyDown={(event) => {
         if (event.key === "Escape") {
@@ -314,11 +320,13 @@ export function ChatPanel({
         }}
       />
       <header className="ai-header">
-        <div>
-          <strong>AI 研究助手</strong>
-          <span>与你一起查看、分析和记录</span>
-        </div>
-        <Button aria-label="收起研究助手" theme="borderless" onClick={onClose}>
+        <h2>AI 研究助手</h2>
+        <Button
+          type="tertiary"
+          aria-label="收起研究助手"
+          theme="borderless"
+          onClick={onClose}
+        >
           收起
         </Button>
       </header>
@@ -337,7 +345,11 @@ export function ChatPanel({
           }}
           disabled={loading}
         />
-        <Button onClick={() => void createConversation()} disabled={loading}>
+        <Button
+          type="tertiary"
+          onClick={() => void createConversation()}
+          disabled={loading}
+        >
           新会话
         </Button>
       </div>
@@ -359,10 +371,11 @@ export function ChatPanel({
         {loading && <Spin />}
         {!chat.messages.length && (
           <div className="ai-empty">
-            <strong>从当前研究出发</strong>
+            <h3>从当前研究出发</h3>
             <p>可以让我筛选 Alpha、解释已有指标，或提出研究记录修改。</p>
             {!conversationId && (
               <Button
+                type="tertiary"
                 onClick={() => void createConversation()}
                 disabled={loading}
               >
@@ -451,7 +464,9 @@ export function ChatPanel({
         <div className="ai-send">
           <small>Enter 发送 · Shift + Enter 换行</small>
           {activeRun ? (
-            <Button onClick={() => void stop()}>停止生成</Button>
+            <Button type="tertiary" onClick={() => void stop()}>
+              停止生成
+            </Button>
           ) : (
             <Button
               theme="solid"
@@ -513,7 +528,7 @@ function BusinessCard({
   const openAlpha = (id: string) =>
     onAction({ type: "open_alpha", alpha_id: id, nonce: Date.now() });
   return (
-    <section className="ai-tool-card">
+    <section className="ai-tool-card" data-status={call.status}>
       <div className="ai-card-title">
         <strong>{toolLabels[call.name] ?? "业务操作"}</strong>
         <Tag
@@ -546,8 +561,14 @@ function BusinessCard({
                     }[key]
                   }
                 </strong>
-                <del>{researchValue(key, target.before[key])}</del>
-                <ins>{researchValue(key, target.after[key])}</ins>
+                <del>
+                  <span>修改前</span>
+                  {researchValue(key, target.before[key])}
+                </del>
+                <ins>
+                  <span>修改后</span>
+                  {researchValue(key, target.after[key])}
+                </ins>
               </div>
             ))}
         </details>
@@ -569,20 +590,29 @@ function BusinessCard({
         </p>
       )}
       {pending && (
-        <div className="inline-actions">
-          <Button
-            theme="solid"
-            disabled={disabled}
-            onClick={() => void onDecision(call.id, true)}
-          >
-            确认执行
-          </Button>
-          <Button
-            disabled={disabled}
-            onClick={() => void onDecision(call.id, false)}
-          >
-            拒绝
-          </Button>
+        <div className="ai-approval">
+          <p className="muted">
+            {call.preview.targets?.length
+              ? `将修改 ${call.preview.targets.length} 条研究记录。`
+              : "将执行以上任务操作。"}
+            确认后执行。
+          </p>
+          <div className="inline-actions">
+            <Button
+              theme="solid"
+              disabled={disabled}
+              onClick={() => void onDecision(call.id, true)}
+            >
+              确认执行
+            </Button>
+            <Button
+              type="tertiary"
+              disabled={disabled}
+              onClick={() => void onDecision(call.id, false)}
+            >
+              拒绝
+            </Button>
+          </div>
         </div>
       )}
       {typeof result.error === "string" && (