feat: 完善差旅票据行程提取与费用明细回填逻辑

增强文档智能识别的票据场景关键词和字段提取能力，优化
会话关联草稿报销单的解析路径，修复费用明细合并和票据
去重边界问题，前端改进报销创建和审批详情交互，补充单
元测试覆盖。

server/tests/test_orchestrator_review_flow.py

@@ -178,3 +178,42 @@ def test_review_next_step_blocked_returns_reasons_and_removes_next_step_action(
             "所属部门未完善" in str(item.get("content") or "")
             for item in review_payload["risk_briefs"]
         )
+
+
+def test_conversation_hydration_does_not_reuse_review_type_for_fresh_expense_prompt() -> None:
+    session_factory = build_session_factory()
+    with session_factory() as db:
+        service = AgentConversationService(db)
+        conversation = service.get_or_create_conversation(
+            conversation_id="conv-review-type-lock",
+            user_id="emp-review-type@example.com",
+            source="user_message",
+            context_json={
+                "session_type": "expense",
+                "draft_claim_id": "claim-old",
+                "attachment_names": ["old-train-ticket.pdf"],
+                "attachment_count": 1,
+                "review_form_values": {
+                    "expense_type": "差旅费",
+                    "business_location": "北京",
+                },
+            },
+        )
+
+        fresh_context = service.hydrate_context_json(
+            conversation=conversation,
+            context_json={},
+            message="业务发生时间:2026-02-20 至 2026-02-23，去上海支持上海电力部署项目，申请报销",
+        )
+        continued_context = service.hydrate_context_json(
+            conversation=conversation,
+            context_json={},
+            message="继续补充酒店发票",
+        )
+
+        assert "draft_claim_id" not in fresh_context
+        assert "attachment_names" not in fresh_context
+        assert "review_form_values" not in fresh_context
+        assert fresh_context["conversation_state"]["review_form_values"]["expense_type"] == "差旅费"
+        assert continued_context["draft_claim_id"] == "claim-old"
+        assert continued_context["review_form_values"]["expense_type"] == "差旅费"