fix: isolate attachment submission state

src/pages/Chat/CodingChatPanel.tsx

@@ -301,7 +301,8 @@ export function CodingChatPanel({
   ]);
 
   const handleAddFiles = useCallback((files: File[]) => {
-    if (!draftKey) return;
+    if (!draftKey
+      || (targetConversationId && submissionFlightsRef.current.has(targetConversationId))) return;
     const accepted: LocalComposerAttachment[] = [];
     const remaining = Math.max(0, CODING_ATTACHMENT_MAX_COUNT - localAttachments.length);
     let validationError = files.length > remaining
@@ -335,10 +336,11 @@ export function CodingChatPanel({
       ...current,
       [draftKey]: [...(current[draftKey] ?? []), ...accepted],
     }));
-  }, [draftKey, localAttachments.length]);
+  }, [draftKey, localAttachments.length, targetConversationId]);
 
   const handleRemoveAttachment = useCallback((id: string) => {
-    if (!draftKey) return;
+    if (!draftKey
+      || (targetConversationId && submissionFlightsRef.current.has(targetConversationId))) return;
     setAttachmentsByDraftKey((current) => {
       const attachment = current[draftKey]?.find((item) => item.id === id);
       if (attachment) URL.revokeObjectURL(attachment.previewUrl);
@@ -349,7 +351,12 @@ export function CodingChatPanel({
     });
     uploadedAttachmentsRef.current.delete(id);
     uploadFlightsRef.current.delete(id);
-  }, [draftKey]);
+    setSubmissionErrors((current) => {
+      const next = { ...current };
+      delete next[draftKey];
+      return next;
+    });
+  }, [draftKey, targetConversationId]);
 
   const prepareAttachments = useCallback(async (
     attachments: LocalComposerAttachment[],

src/pages/Chat/CodingComposer.tsx

@@ -91,6 +91,7 @@ export function CodingComposer({
         type="file"
         accept="image/png,image/jpeg,image/webp,image/gif"
         multiple
+        disabled={!editable || submitting}
         className="sr-only"
         data-testid="coding-file-attachment-input"
         onChange={(event) => {
@@ -110,8 +111,9 @@ export function CodingComposer({
                 />
                 <button
                   type="button"
-                  className="absolute right-1 top-1 flex h-10 w-10 translate-x-2 -translate-y-2 items-end justify-start rounded-full bg-foreground/85 p-1.5 text-background transition-[background-color,scale] duration-150 ease-out hover:bg-foreground active:scale-[0.96]"
+                  className="absolute right-1 top-1 flex h-10 w-10 translate-x-2 -translate-y-2 items-end justify-start rounded-full bg-foreground/85 p-1.5 text-background transition-[background-color,scale] duration-150 ease-out hover:bg-foreground active:scale-[0.96] disabled:cursor-not-allowed disabled:opacity-60"
                   aria-label={`移除图片 ${attachment.name}`}
+                  disabled={submitting}
                   onClick={() => onRemoveAttachment(attachment.id)}
                 >
                   <X className="h-3.5 w-3.5" aria-hidden="true" />
@@ -133,6 +135,7 @@ export function CodingComposer({
             if (canSend) onSubmit();
           }}
           onPaste={(event) => {
+            if (submitting) return;
             const files = Array.from(event.clipboardData.files).filter((file) => file.type.startsWith('image/'));
             if (files.length > 0) onAddFiles(files);
           }}