feat: 新增预算费控模型与报销审批流引擎

后端新增预算费控服务和报销单审批流模块，引入申请人费用画像
算法，优化知识库 RAG 运行时和同步逻辑，完善报销单工作流常
量和明细同步，更新差旅报销规则电子表格，前端新增预算分析
组件和数字员工模型，完善审批对话框和洞察面板交互，优化侧
边栏和顶栏样式，补充单元测试。

server/src/app/schemas/budget.py

@@ -2,6 +2,7 @@ from __future__ import annotations
 
 from datetime import datetime
 from decimal import Decimal
+from typing import Any
 
 from pydantic import BaseModel, ConfigDict, Field
 
@@ -144,6 +145,17 @@ class BudgetCheckRead(BaseModel):
     allocation: BudgetAllocationRead | None = None
 
 
+class BudgetClaimAnalysisRead(BaseModel):
+    budget_context: dict[str, Any] = Field(default_factory=dict)
+    score: int
+    rating: str
+    risk_level: str
+    summary: str
+    metrics: dict[str, Any] = Field(default_factory=dict)
+    basis: list[str] = Field(default_factory=list)
+    suggestions: list[str] = Field(default_factory=list)
+
+
 class BudgetOperationRead(BaseModel):
     ok: bool
     message: str