修复: 打通设计回复流式投递与结构化确认

问题：Run 完成会抢在 SSE 流式事件之前清空 pending，导致回复整块出现；无 Quote 的确认按钮又会降级为普通聊天，因此无法创建任务。

实现：为 Main 事件队列增加有界投递屏障，严格识别生成确认短语并只调用结构化 Quote Action，接入 generation capability 提示，同时补齐竞态、误触和任务对账测试。

src/pages/ImageCanvas/index.tsx

@@ -37,6 +37,21 @@ import type {
 } from '../../../shared/image-workspace';
 
 const ACTIVE_TASK_STATUSES = new Set<DesignTaskStatus>(['queued', 'running']);
+const CONFIRMATION_UNAVAILABLE_MESSAGE = (
+  '当前没有可确认的生成报价，请先让设计 Agent 完成方案与报价。'
+);
+const GENERATION_CONFIRMATION_INTENTS = new Set([
+  '确认生成',
+  '确认开始生成',
+  '确认并开始生成',
+  '确认开始制作',
+  '确认并开始制作',
+]);
+
+function isGenerationConfirmationIntent(message: string): boolean {
+  const normalized = message.trim().replace(/[\s，,。.!！?？、]/g, '');
+  return GENERATION_CONFIRMATION_INTENTS.has(normalized);
+}
 
 function taskStatusLabel(status: DesignTaskStatus): string {
   if (status === 'queued') return '排队中';
@@ -211,6 +226,7 @@ export function ImageCanvas() {
     () => workspace ? activeQuote(workspace.messages) : null,
     [workspace],
   );
+  const generationAvailable = bootstrap?.capabilities.generation ?? false;
   const conversationMessages = useMemo<RenderedDesignMessage[]>(() => {
     if (!workspace) return [];
     const messages: RenderedDesignMessage[] = [...workspace.messages];
@@ -259,9 +275,37 @@ export function ImageCanvas() {
     }
   }, [conversationMessages.length, pendingTurn?.assistantText]);
 
+  const handleConfirm = async (quoteId: string) => {
+    if (!workspace || confirmingQuoteId) return;
+    if (!generationAvailable) {
+      setActionError(CONFIRMATION_UNAVAILABLE_MESSAGE);
+      return;
+    }
+    const requestedWorkspaceId = workspace.workspaceId;
+    setConfirmingQuoteId(quoteId);
+    setActionError(null);
+    try {
+      await confirmGeneration(quoteId);
+    } catch (error) {
+      if (useImageWorkspaceStore.getState().activeWorkspaceId !== requestedWorkspaceId) return;
+      setActionError(error instanceof Error ? error.message : String(error));
+    } finally {
+      setConfirmingQuoteId(null);
+    }
+  };
+
   const handleSend = async (override?: string) => {
     const message = (override ?? prompt).trim();
     if (!workspace || !message || submitting) return;
+    if (isGenerationConfirmationIntent(message)) {
+      setPrompt('');
+      if (quote && generationAvailable) {
+        await handleConfirm(quote.quoteId);
+      } else {
+        setActionError(CONFIRMATION_UNAVAILABLE_MESSAGE);
+      }
+      return;
+    }
     const requestedWorkspaceId = workspace.workspaceId;
     setSubmitting(true);
     setActionError(null);
@@ -277,21 +321,6 @@ export function ImageCanvas() {
     }
   };
 
-  const handleConfirm = async (quoteId: string) => {
-    if (!workspace || confirmingQuoteId) return;
-    const requestedWorkspaceId = workspace.workspaceId;
-    setConfirmingQuoteId(quoteId);
-    setActionError(null);
-    try {
-      await confirmGeneration(quoteId);
-    } catch (error) {
-      if (useImageWorkspaceStore.getState().activeWorkspaceId !== requestedWorkspaceId) return;
-      setActionError(error instanceof Error ? error.message : String(error));
-    } finally {
-      setConfirmingQuoteId(null);
-    }
-  };
-
   const handleComposerKeyDown = (event: KeyboardEvent<HTMLTextAreaElement>) => {
     if ((event.metaKey || event.ctrlKey) && event.key === 'Enter') {
       event.preventDefault();
@@ -469,11 +498,16 @@ export function ImageCanvas() {
                                     size="sm"
                                     className="h-8 rounded-full px-3 text-xs font-semibold"
                                     onClick={() => {
-                                      if (reply.includes('确认') && quote) {
-                                        void handleConfirm(quote.quoteId);
-                                      } else {
+                                      if (!isGenerationConfirmationIntent(reply)) {
                                         setPrompt(reply);
+                                        return;
                                       }
+                                      if (quote && generationAvailable) {
+                                        void handleConfirm(quote.quoteId);
+                                        return;
+                                      }
+                                      setPrompt('');
+                                      setActionError(CONFIRMATION_UNAVAILABLE_MESSAGE);
                                     }}
                                   >
                                     {reply}
@@ -502,6 +536,11 @@ export function ImageCanvas() {
           >
             <div className="mx-auto w-full max-w-3xl">
               <div className="chat-composer-surface rounded-2xl border border-border/70 bg-background p-3 shadow-soft focus-within:ring-1 focus-within:ring-foreground/10">
+                {!generationAvailable ? (
+                  <p className="mb-2 rounded-xl bg-amber-500/10 px-3 py-2 text-xs font-semibold text-amber-700 dark:text-amber-300">
+                    当前环境仅支持设计沟通，图片/视频生成能力尚未启用。
+                  </p>
+                ) : null}
                 <Textarea
                   aria-label="设计需求"
                   value={prompt}