feat: 账套模式全量接入 — 12个API entity_id统一走token解析链 + 前端登录选公司/切换器重签token

- 后端: kpis/bsc_layers/cash/predict/growth_quality/tax_compliance/data 的 entity_id 参数统一改为 Depends(get_entity_id)
- 前端: 拦截器删除自动附加X-Entity-Id/entity_id; 登录页公司选择器(按用户名授权过滤); 切换器改POST /auth/switch-entity重新签发token+整页刷新; ReportCenter同步改造
- 修复前后端不匹配: login-entities路由→/auth/entities; login响应entity_id取user.entity_id

backend/app/api/data.py

@@ -7,6 +7,7 @@ from sqlalchemy.orm import Session
 from sqlalchemy import func
 from typing import Optional
 from app.database import get_db
+from app.deps import get_entity_id
 from app.auth_middleware import require_auth, require_role
 from app.models import KPIValue, DataSourceConfig, OperationLog, KPIDefinition
 
@@ -165,7 +166,7 @@ def _smart_detect_statement_type(filename: str) -> str | None:
 @router.post("/import-excel-smart")
 async def import_excel_smart(
     file: UploadFile = File(...),
-    entity_id: int = Form(1),
+    entity_id: int = Depends(get_entity_id),
     db: Session = Depends(get_db),
 ):
     """智能导入 — BOT自动识别列名/期间/报表类型，无需手动映射"""