fix: harden detail plan image-link fallback and model send sync

app/api/canvas/detail-plan/route.ts

@@ -39,6 +39,19 @@ function isAbortError(error: unknown): boolean {
   );
 }
 
+function isReferenceImageDownloadError(error: unknown): boolean {
+  const target = error as { name?: unknown; message?: unknown };
+  const name = String(target?.name || "");
+  const message = String(target?.message || "");
+  return (
+    /AI_DownloadError/i.test(name) ||
+    /Failed to download/i.test(message) ||
+    /404\s*Not\s*Found/i.test(message) ||
+    /403\s*Forbidden/i.test(message) ||
+    /image.*download/i.test(message)
+  );
+}
+
 function supportsVisionPlanning(model: {
   supportsVision?: boolean | null;
   capabilities?: unknown;
@@ -1849,12 +1862,15 @@ export async function POST(request: Request) {
       if (
         isAbortError(error) ||
         /invalid scheme/i.test(message) ||
+        isReferenceImageDownloadError(error) ||
         /operationtimeouterror|timed out|timeout/i.test(message)
       ) {
         console.error("[Canvas Detail Plan] Primary planning aborted, fallback applied:", error);
         const fallbackReason = /invalid scheme/i.test(message)
           ? "规划模型图片输入协议不兼容，已回退到稳定分镜模板。"
-          : "规划模型调用超时，已自动回退到稳定分镜模板。";
+          : isReferenceImageDownloadError(error)
+            ? "参考图链接不可访问（404/下载失败），已自动忽略参考图并回退稳定分镜模板。"
+            : "规划模型调用超时，已自动回退到稳定分镜模板。";
         return NextResponse.json({
           success: true,
           data: {

components/canvas/CanvasChatPanel.tsx

@@ -6450,14 +6450,18 @@ export function CanvasChatPanel({ chatId, initialMessages = [], onClose, onOpenF
                         }}
                         disabled={isDetailGenerating}
                         className={cn(
-                          "rounded-lg border px-3 py-2 text-left transition-colors",
+                          "rounded-lg border px-3 py-2 text-left transition-all duration-150",
                           isDetailGenerating && "cursor-not-allowed opacity-60",
                           selected
-                            ? "border-primary/50 bg-primary/10 text-primary"
-                            : "border-border/50 bg-background text-muted-foreground hover:border-primary/30 hover:text-foreground"
+                            ? "border-[#5b7cff] bg-[#eef3ff] text-[#2f57d8] shadow-[0_0_0_1px_rgba(91,124,255,0.28)]"
+                            : "border-border/60 bg-background text-muted-foreground hover:border-[#9fb3ff] hover:bg-[#f8faff] hover:text-foreground"
                         )}
+                        aria-pressed={selected}
                       >
-                        <div className="text-[11px] font-medium">{option.label}</div>
+                        <div className="flex items-center justify-between">
+                          <div className="text-[11px] font-medium">{option.label}</div>
+                          {selected ? <Check className="h-3.5 w-3.5" /> : null}
+                        </div>
                         <div className="mt-1 text-[10px] leading-snug opacity-80">
                           {option.description}
                         </div>