merge: 合并 origin/xuhd，解决 message-list-item 和 WorkspaceRoutes 冲突

- message-list-item: 保留 EmbeddedPageContext + 消息内联编辑两套功能
- WorkspaceRoutes: 保留 IframeChatPage + NotebookDetailPageWithKey

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

frontend-web/src/components/ai-elements/artifact.tsx

@@ -16,7 +16,7 @@ export type ArtifactProps = HTMLAttributes<HTMLDivElement>;
 export const Artifact = ({ className, ...props }: ArtifactProps) => (
   <div
     className={cn(
-      "flex flex-col overflow-hidden rounded-[1.35rem] border border-[#ece7dd] bg-white shadow-[0_24px_60px_-28px_rgba(15,23,42,0.16)] ring-1 ring-black/3",
+      "flex flex-col overflow-hidden rounded-[1.35rem] border border-border bg-background shadow-[0_24px_60px_-28px_rgba(15,23,42,0.16)] ring-1 ring-black/3",
       className,
     )}
     {...props}
@@ -31,7 +31,7 @@ export const ArtifactHeader = ({
 }: ArtifactHeaderProps) => (
   <div
     className={cn(
-      "flex items-center justify-between border-b border-[#efe9de] bg-white px-4 py-3",
+      "flex items-center justify-between border-b border-border bg-background px-4 py-3",
       className,
     )}
     {...props}
@@ -147,7 +147,7 @@ export const ArtifactContent = forwardRef<HTMLDivElement, ArtifactContentProps>(
     <div
       ref={ref}
       className={cn(
-        "min-h-0 flex-1 overflow-auto bg-white p-4",
+        "min-h-0 flex-1 overflow-auto bg-background p-4",
         className,
       )}
       {...props}

frontend-web/src/components/workspace/chats/chat-box.tsx

@@ -384,14 +384,14 @@ const ChatBox: React.FC<{
       />
       <ResizablePanel
         className={cn(
-          "bg-[#fffdfa] transition-all duration-300 ease-in-out",
+          "bg-background transition-all duration-300 ease-in-out",
           !sidePanelOpen && "opacity-0",
         )}
         id="artifacts"
       >
         <div
           className={cn(
-            "h-full bg-[#fffdfa] p-4 transition-transform duration-300 ease-in-out",
+            "h-full bg-background p-4 transition-transform duration-300 ease-in-out",
             sidePanelOpen ? "translate-x-0" : "translate-x-full",
           )}
         >

frontend-web/src/components/workspace/messages/message-list-item.tsx

@@ -371,6 +371,18 @@ function MessageContent_({
   onEditResubmit?: (text: string) => void;
 }) {
   const baseRehypePlugins = useRehypeSplitWordsIntoSpans(isLoading);
+
+  // Streamdown splits content into per-block processors; calling the factory
+  // once here ensures all blocks share the same transformer instance (and thus
+  // the same citation counter) for this message.
+  const stableExtraPlugins = useMemo(() => {
+    if (!extraRehypePlugins?.length) return [];
+    return extraRehypePlugins.map((factory) => {
+      const transformer = factory();
+      return () => transformer;
+    });
+  }, [extraRehypePlugins]);
+
   const rehypePlugins = useMemo(
     () =>
       extraRehypePlugins?.length

frontend-web/src/components/workspace/workspace-nav-chat-list.tsx

@@ -19,6 +19,9 @@ import { BotIcon, BrainIcon, ListChecks, MessageSquarePlus, MessagesSquare, PenL
 import { SidebarCollapseButton } from "./workspace-header";
 import { WorkspaceNavStudio } from "./workspace-nav-studio";
 import { cn } from "@/lib/utils";
+import { env } from "@/env";
+
+const studioEnabled = env.STUDIO_ENABLED?.toLowerCase() === "true";
 
 // 普通导航项：默认中性色，激活态与「新对话」一致——主色浅底 + 主色文字/图标
 const NAV_ITEM_CLASS =
@@ -165,7 +168,7 @@ export function WorkspaceNavChatList({
         )}
       </SidebarMenu>
     </SidebarGroup>
-    {/* {!showCollapseTrigger && <WorkspaceNavStudio />} */}
+    {!showCollapseTrigger && studioEnabled && <WorkspaceNavStudio />}
     </>
   );
 }

frontend-web/src/components/workspace/workspace-nav-studio.tsx

@@ -34,8 +34,6 @@ const NAV_ITEM_CLASS =
   "data-[active=true]:bg-primary/15 data-[active=true]:text-primary data-[active=true]:shadow-none " +
   "dark:hover:bg-primary/15 dark:data-[active=true]:bg-primary/25 dark:data-[active=true]:text-primary-foreground";
 
-const SIDEBAR_PREVIEW_COUNT = 5;
-
 export function WorkspaceNavStudio() {
   const { notebooks, isLoading, isError } = useStudioNotebooks();
   const { pathname } = useLocation();
@@ -71,6 +69,7 @@ export function WorkspaceNavStudio() {
     return null;
   }
 
+  const SIDEBAR_PREVIEW_COUNT = 2;
   const preview = notebooks.slice(0, SIDEBAR_PREVIEW_COUNT);
 
   return (