feat: preserve isolated visitor agent runtime

tests/unit/worker/test_runtime_worker_dispatch.py

@@ -4,6 +4,7 @@ from unittest.mock import AsyncMock
 
 import pytest
 
+from app.core.contracts import AgentResult, CoreResult, RequestContext
 from app.service.memory_recall_service import MemoryRecallService
 from app.service.model_gateway import ModelGenerationService
 from app.worker.runtime import WorkerRuntime
@@ -22,6 +23,40 @@ OUTBOX = {
 }
 
 
+@pytest.mark.asyncio
+async def test_worker_restores_visitor_without_identity_repository_call() -> None:
+    """访客异步任务只能恢复最小公开上下文，不能查询正式身份库。"""
+    runtime = WorkerRuntime.__new__(WorkerRuntime)
+    runtime.resolve_identity = AsyncMock(side_effect=AssertionError("identity lookup is forbidden"))
+
+    context = await runtime.restore_context(
+        actor_type="visitor", actor_id="visitor:test", trace_id="trace-test"
+    )
+
+    assert context.roles == ("visitor",)
+    assert context.permissions == ("agent:run",)
+    assert context.data_scope == "public"
+    runtime.resolve_identity.assert_not_awaited()
+
+
+def test_visitor_does_not_request_memory_extraction() -> None:
+    """访客消息即使包含偏好信号，也不能进入客户记忆抽取队列。"""
+    context = RequestContext(
+        user_id="visitor:test", trace_id="visitor-trace", roles=("visitor",),
+        permissions=("agent:run",), data_scope="public",
+    )
+    result = AgentResult(run_id="visitor-run", result=CoreResult(text="公开答复"))
+
+    requested = WorkerRuntime.should_request_memory_extraction(
+        context=context,
+        message="我的风险偏好是稳健型",
+        result=result,
+        business_events=(),
+    )
+
+    assert requested is False
+
+
 class FakeSession(AbstractAsyncContextManager["FakeSession"]):
     def __init__(self) -> None:
         self.scalar = AsyncMock(return_value="event-1")