feat: 支持会话内补传资料并保持绑定

tests/test_chat.py

@@ -1,4 +1,5 @@
 from django.urls import reverse
+from django.core.files.uploadedfile import SimpleUploadedFile
 
 from agent_core.results import AgentResult
 from apps.audit.models import AgentAuditLog
@@ -325,3 +326,40 @@ def test_chat_page_shows_upload_entry_and_dynamic_context_cards(client, db):
     assert "是否允许正式导出" in content
     assert "通知状态" in content
     assert "飞书通知 / 待处理" in content
+
+
+def test_chat_upload_keeps_existing_conversation_binding_and_adds_documents(client, db):
+    batch, conversation = _create_conversation_with_batch()
+    existing_document = UploadedDocument.objects.create(
+        batch=batch,
+        scenario_id="document_review",
+        original_name="原说明书.md",
+        file_type="md",
+        size=1,
+        status=UploadedDocument.STATUS_INDEXED,
+    )
+    existing_count = UploadedDocument.objects.filter(batch=batch).count()
+    upload_file = SimpleUploadedFile(
+        "新增补充资料.txt",
+        "产品名称：新型冠状病毒 2019-nCoV 核酸检测试剂盒".encode("utf-8"),
+        content_type="text/plain",
+    )
+
+    response = client.post(
+        reverse("chat:upload-documents", args=[conversation.conversation_id]),
+        {"files": [upload_file]},
+        follow=True,
+    )
+
+    content = response.content.decode("utf-8")
+    batch.refresh_from_db()
+    conversation.refresh_from_db()
+    assert response.status_code == 200
+    assert SubmissionBatch.objects.count() == 1
+    assert Conversation.objects.count() == 1
+    assert conversation.conversation_id == "conv-001"
+    assert batch.conversation_id == conversation.conversation_id
+    assert UploadedDocument.objects.filter(batch=batch).count() == existing_count + 1
+    assert UploadedDocument.objects.filter(batch=batch, original_name="新增补充资料.txt").exists()
+    assert "新增补充资料.txt" in content
+    assert "已补充到当前资料包" in content