feat: 新增预算后端服务与差旅风险规则库

后端新增预算模型、端点和服务模块，支持预算 CRUD 和余额
查询，清理旧生成规则文件并替换为按严重等级分类的差旅风
险规则库，优化认证权限和报销单访问策略，新增财务规则目
录和演示数据构建脚本，前端预算中心增加对话框交互，完善
审计页面运行时模型和元数据展示，补充单元测试。

server/src/app/schemas/budget.py

@@ -0,0 +1,120 @@
+from __future__ import annotations
+
+from datetime import datetime
+from decimal import Decimal
+
+from pydantic import BaseModel, ConfigDict, Field
+
+
+class BudgetAllocationCreate(BaseModel):
+    fiscal_year: int = Field(ge=2000, le=2100)
+    period_type: str = Field(default="quarter", max_length=20)
+    period_key: str = Field(min_length=1, max_length=30)
+    department_id: str | None = Field(default=None, max_length=36)
+    department_name: str = Field(min_length=1, max_length=100)
+    cost_center: str | None = Field(default=None, max_length=50)
+    project_code: str | None = Field(default=None, max_length=50)
+    subject_code: str = Field(min_length=1, max_length=50)
+    subject_name: str = Field(min_length=1, max_length=100)
+    original_amount: Decimal = Field(ge=0)
+    warning_threshold: Decimal = Field(default=Decimal("80.00"), ge=0, le=100)
+    control_action: str = Field(default="block", max_length=30)
+    description: str | None = Field(default=None, max_length=500)
+
+
+class BudgetCheckRequest(BaseModel):
+    fiscal_year: int | None = Field(default=None, ge=2000, le=2100)
+    period_key: str | None = Field(default=None, max_length=30)
+    department_id: str | None = Field(default=None, max_length=36)
+    department_name: str | None = Field(default=None, max_length=100)
+    cost_center: str | None = Field(default=None, max_length=50)
+    project_code: str | None = Field(default=None, max_length=50)
+    subject_code: str = Field(min_length=1, max_length=50)
+    amount: Decimal = Field(ge=0)
+
+
+class BudgetOperationRequest(BudgetCheckRequest):
+    source_type: str = Field(min_length=1, max_length=40)
+    source_id: str = Field(min_length=1, max_length=64)
+    source_no: str = Field(min_length=1, max_length=80)
+    reason: str | None = Field(default=None, max_length=500)
+
+
+class BudgetBalanceRead(BaseModel):
+    total_amount: Decimal
+    reserved_amount: Decimal
+    consumed_amount: Decimal
+    available_amount: Decimal
+    usage_rate: Decimal
+
+
+class BudgetAllocationRead(BaseModel):
+    model_config = ConfigDict(from_attributes=True)
+
+    id: str
+    budget_no: str
+    fiscal_year: int
+    period_type: str
+    period_key: str
+    department_id: str | None
+    department_name: str
+    cost_center: str | None
+    project_code: str | None
+    subject_code: str
+    subject_name: str
+    original_amount: Decimal
+    adjusted_amount: Decimal
+    status: str
+    warning_threshold: Decimal
+    control_action: str
+    description: str | None = None
+    balance: BudgetBalanceRead
+    created_at: datetime
+    updated_at: datetime
+
+
+class BudgetTransactionRead(BaseModel):
+    model_config = ConfigDict(from_attributes=True)
+
+    id: str
+    transaction_no: str
+    allocation_id: str
+    reservation_id: str | None
+    source_type: str
+    source_id: str
+    source_no: str
+    transaction_type: str
+    amount: Decimal
+    before_available_amount: Decimal
+    after_available_amount: Decimal
+    operator: str | None
+    reason: str | None
+    created_at: datetime
+
+
+class BudgetSummaryRead(BaseModel):
+    fiscal_year: int | None = None
+    period_key: str | None = None
+    total_amount: Decimal
+    reserved_amount: Decimal
+    consumed_amount: Decimal
+    available_amount: Decimal
+    warning_count: int
+    over_budget_count: int
+    allocations: list[BudgetAllocationRead] = Field(default_factory=list)
+
+
+class BudgetCheckRead(BaseModel):
+    passed: bool
+    blocking_reasons: list[str] = Field(default_factory=list)
+    flags: list[dict] = Field(default_factory=list)
+    allocation: BudgetAllocationRead | None = None
+
+
+class BudgetOperationRead(BaseModel):
+    ok: bool
+    message: str
+    reservation_id: str | None = None
+    allocation: BudgetAllocationRead | None = None
+    transaction: BudgetTransactionRead | None = None
+    flags: list[dict] = Field(default_factory=list)

server/src/app/schemas/settings.py

@@ -23,7 +23,7 @@ class SettingsCompanyForm(BaseModel):
 
 class SettingsAdminForm(BaseModel):
     adminAccount: str = Field(min_length=1, max_length=120)
-    adminEmail: str = Field(min_length=1, max_length=255)
+    adminEmail: str = Field(default="", max_length=255)
     newPassword: str = Field(default="", max_length=128)
     confirmPassword: str = Field(default="", max_length=128)
     sessionTimeout: int = Field(default=30, ge=5, le=240)