feat(frontend): 优化工作区输入框与 artifacts 展示体验

改进工作区核心交互，提升输入与结果查看的一致性和可用性。

调整 prompt 输入相关组件逻辑，优化输入行为与状态反馈
更新 workspace input-box 交互细节，改善可用性与稳定性
优化 message-group 展示逻辑，增强消息区域可读性
调整 artifact-file-detail 预览相关实现，为后续 Office 文件展示做准备
补充并更新 thread-routing e2e 用例，覆盖关键路由与交互回归场景

frontend/src/components/ai-elements/prompt-input.tsx

@@ -883,7 +883,7 @@ export const PromptInputTextarea = ({
       if (!submitOnEnter) {
         return;
       }
-      if (e.shiftKey) {
+      if (e.shiftKey || e.ctrlKey || e.metaKey) {
         return;
       }
       e.preventDefault();
@@ -1089,10 +1089,12 @@ export const PromptInputSubmit = ({
       controller.attachments.files.length > 0
     : false;
 
-  // 正在 streaming 时不允许发送
-  const isStreaming = status === "streaming" || status === "submitted";
-
-  const isDisabled = disabled || !hasContent || isStreaming;
+  const isStreaming = status === "streaming";
+  const isSubmitted = status === "submitted";
+  // Streaming 时按钮用于停止，不受输入内容是否为空限制
+  const isDisabled = isStreaming
+    ? !!disabled
+    : disabled || !hasContent || isSubmitted;
 
   let Icon = <ArrowUpIcon className="size-4" />;
 

frontend/src/components/workspace/artifacts/artifact-file-detail.tsx

@@ -95,8 +95,8 @@ export function ArtifactFileDetail({
     return checkCodeFile(filepath);
   }, [filepath, isWriteFile, isSkillFile]);
   const previewable = useMemo(() => {
-    return (language === "html" && !isWriteFile) || language === "markdown";
-  }, [isWriteFile, language]);
+    return language === "html" || language === "markdown";
+  }, [language]);
   const artifactUrl = useMemo(() => {
     if (!threadId) {
       return "";

frontend/src/components/workspace/input-box.tsx

@@ -342,7 +342,6 @@ export function InputBox({
               "size-full",
               !effectiveIsFocused && "h-[80px] py-0 leading-20",
             )}
-            submitOnEnter={false}
             disabled={isInputDisabled}
             placeholder={t.inputBox.placeholder}
             autoFocus={autoFocus}

frontend/src/components/workspace/messages/message-group.tsx

@@ -76,6 +76,9 @@ export function MessageGroup({
       return filteredSteps[filteredSteps.length - 1];
     }
   }, [lastToolCallStep, steps]);
+  const totalToolStepCount = aboveLastToolCallSteps.length + (lastToolCallStep ? 1 : 0);
+  const shouldShowToolSteps = !!lastToolCallStep &&
+    (showAbove || aboveLastToolCallSteps.length === 0);
   const rehypePlugins = useRehypeSplitWordsIntoSpans(isLoading);
   return (
     <ChainOfThought
@@ -87,14 +90,17 @@ export function MessageGroup({
           key="above"
           className="w-full items-start justify-start text-left"
           variant="ghost"
-          onClick={() => setShowAbove(!showAbove)}
+          onClick={(event) => {
+            event.stopPropagation();
+            setShowAbove((prev) => !prev);
+          }}
         >
           <ChainOfThoughtStep
             label={
               <span className="opacity-60">
                 {showAbove
                   ? t.toolCalls.lessSteps
-                  : t.toolCalls.moreSteps(aboveLastToolCallSteps.length)}
+                  : t.toolCalls.moreSteps(totalToolStepCount)}
               </span>
             }
             icon={
@@ -108,7 +114,7 @@ export function MessageGroup({
           ></ChainOfThoughtStep>
         </Button>
       )}
-      {lastToolCallStep && (
+      {shouldShowToolSteps && (
         <ChainOfThoughtContent className="px-4 pb-2">
           {showAbove &&
             aboveLastToolCallSteps.map((step) =>
@@ -145,7 +151,10 @@ export function MessageGroup({
             key={lastReasoningStep.id}
             className="w-full items-start justify-start text-left"
             variant="ghost"
-            onClick={() => setShowLastThinking(!showLastThinking)}
+            onClick={(event) => {
+              event.stopPropagation();
+              setShowLastThinking((prev) => !prev);
+            }}
           >
             <div className="flex w-full items-center justify-between">
               <ChainOfThoughtStep

frontend/tests/e2e/thread-routing.spec.ts

@@ -78,4 +78,25 @@ test.describe("线程路由（无 isnew）", () => {
       { timeout: 30_000 },
     );
   });
+
+  test("streaming 中点击停止可中断输出", async ({ page }) => {
+    const threadId = uuid();
+    const text =
+      "请逐行输出 1 到 500 的数字，并在每一行前面加上“第N行：”前缀，不要省略。";
+
+    await openChat(page, newChatEntry(threadId));
+    await expect(page.getByTestId("welcome-suggestions")).toBeVisible();
+
+    await sendMessage(page, text);
+
+    const submitButton = page.locator("button[aria-label='Submit']");
+
+    await expect(submitButton).toHaveText("停止", { timeout: 30_000 });
+    await expect(submitButton).toBeEnabled();
+
+    await submitButton.click();
+
+    // 点击停止后应退出 streaming 态，按钮文本不再是“停止”
+    await expect(submitButton).toHaveText("发送", { timeout: 30_000 });
+  });
 });