feat(chat): allow knowledge chat before upload

apps/chat/services.py

@@ -28,6 +28,23 @@ def create_conversation_for_batch(batch_id: str, product_name: str) -> Conversat
     return conversation
 
 
+def create_knowledge_conversation() -> Conversation:
+    """
+    创建未绑定资料包的知识库问答会话。
+
+    该会话用于用户尚未上传资料时直接向 RAG 知识库提问，
+    因此 batch_id 与 product_name 保持为空，Agent Core 通过空范围执行全局检索。
+    """
+    return Conversation.objects.create(
+        conversation_id=_generate_conversation_id(),
+        title="知识库问答会话",
+        product_name="",
+        batch_id="",
+        task_status=Conversation.STATUS_PENDING,
+        node_results=_build_knowledge_node_results(),
+    )
+
+
 def execute_conversation_agent(
     *,
     conversation: Conversation,
@@ -132,6 +149,14 @@ def _build_initial_node_results() -> list[dict]:
     ]
 
 
+def _build_knowledge_node_results() -> list[dict]:
+    return [
+        {"code": "knowledge_retrieval", "label": "知识库检索", "status": "待处理"},
+        {"code": "answer_generation", "label": "问答生成", "status": "待处理"},
+        {"code": "risk", "label": "风险预警", "status": "待处理"},
+    ]
+
+
 def _persist_notification_records(result: AgentResult, *, web_detail_url: str = "") -> None:
     payload = result.notification_payload or {}
     owners = payload.get("owners") or []

apps/chat/views.py

@@ -9,7 +9,11 @@ from apps.documents.services import append_documents_to_batch
 
 from .forms import ChatForm, ConversationUploadForm
 from .models import Conversation
-from .services import execute_conversation_agent, execute_conversation_export
+from .services import (
+    create_knowledge_conversation,
+    execute_conversation_agent,
+    execute_conversation_export,
+)
 
 RISK_LEVEL_DISPLAY = {
     "high": "高",
@@ -48,19 +52,48 @@ def index(request):
     conversations = Conversation.objects.all()
     if conversations.exists():
         return redirect("chat:detail", conversation_id=conversations.first().conversation_id)
+    documents = UploadedDocument.objects.filter(batch__isnull=True)
+    form = ChatForm(request.POST or None, documents=documents)
+    upload_form = ConversationUploadForm()
+    result = None
+    audit_log = None
+    conversation = None
+    if request.method == "POST" and form.is_valid():
+        conversation = create_knowledge_conversation()
+        result, audit_log = execute_conversation_agent(
+            conversation=conversation,
+            message=form.cleaned_data["message"],
+            document_ids=form.cleaned_data["document_ids"],
+            detail_url_builder=lambda log_id: reverse("audit:detail", args=[log_id]),
+        )
+        conversation.refresh_from_db()
+        documents = UploadedDocument.objects.filter(batch__isnull=True)
+
+    display_node_results = _normalize_node_results(conversation.node_results if conversation else [])
+    workspace_summary = _build_workspace_summary(conversation, None, display_node_results) if conversation else _build_empty_workspace_summary()
     return render(
         request,
         "chat/index.html",
         {
-            "conversation": None,
+            "conversation": conversation,
             "conversations": [],
             "conversation_history": [],
-            "form": ChatForm(),
-            "documents": [],
-            "result": None,
-            "audit_log": None,
-            "node_results": [],
+            "batch": None,
+            "form": form,
+            "documents": documents,
+            "document_count": documents.count(),
+            "result": result,
+            "audit_log": audit_log,
+            "node_results": display_node_results,
             "active_node": None,
+            "workspace_summary": workspace_summary,
+            "conversation_context": _build_conversation_context(conversation, None, workspace_summary) if conversation else {},
+            "prompt_templates": _build_prompt_templates(),
+            "analysis_card": _build_analysis_card(result, conversation) if conversation else {},
+            "upload_form": upload_form,
+            "export_card": _build_export_card(result, conversation) if conversation else {},
+            "risk_card": _build_risk_card(result, conversation) if conversation else {},
+            "notify_card": _build_notify_card(result, conversation) if conversation else {},
         },
     )
 
@@ -201,6 +234,18 @@ def _build_workspace_summary(
     }
 
 
+def _build_empty_workspace_summary() -> dict:
+    return {
+        "highest_risk_level": "-",
+        "export_allowed": "否",
+        "notify_status": "待处理",
+        "export_status": "待处理",
+        "download_url": "",
+        "file_count": 0,
+        "page_count": 0,
+    }
+
+
 def _build_conversation_context(
     conversation: Conversation,
     batch: SubmissionBatch | None,