feat(dashboard): 工作台四区块实时聚合与风险预警参数

- 后端 /api/v1/dashboard 单端点返回四区块：经营总览（绩效/应付/人数/团队数/月结状态/近 6 个月趋势）、待办（待审批 + 回款未指定批次 + 同步显式降级）、风险预警（回款逾期/审批超时，阈值参数化）、最近动态（操作日志）
- dashboard_service 实时派生（不落表、不引调度器）；参数快照一次解析；总览只做 SQL 聚合，不复用报表的重查询
- V10 迁移新增预警参数三项（warning.enabled / warning.receipt.overdue.days=90 / warning.approval.timeout.days=3），参数注册表 19→22，init-dev 与 V10 SQL 双轨同步
- 测试：test_dashboard 5 例（权限文案/总览对账+非法月份 400/待办三类/预警命中与参数关闭/动态来源）；全量 852 passed
- 依赖闭包并入：core/month.py 月份校验、api/v1/base/business_roles.py（router 已挂载的岗位只读端点）、test_month_validation
- 修复：alembic --sql 在 Windows 按控制台 GBK 输出，V10 SQL 以 UTF-8 重新导出（README 已记）

Co-Authored-By: Claude Code <noreply@anthropic.com>

backend/app/api/router.py

@@ -8,6 +8,7 @@ from fastapi import APIRouter
 
 from app.api import health
 from app.api.v1 import auth
+from app.api.v1.base import business_roles as base_business_roles
 from app.api.v1.base import customers as base_customers
 from app.api.v1.base import personnel as base_personnel
 from app.api.v1.base import products as base_products
@@ -16,6 +17,7 @@ from app.api.v1.business import ratings as business_ratings
 from app.api.v1.business import receipts as business_receipts
 from app.api.v1.business import shipments as business_shipments
 from app.api.v1.calc import router as calc_router
+from app.api.v1.dashboard import router as dashboard_router
 from app.api.v1.reports import router as reports_router
 from app.api.v1.settlements import router as settlements_router
 from app.api.v1.system import approvals as system_approvals
@@ -52,6 +54,7 @@ base_router = APIRouter(prefix="/base")
 base_router.include_router(base_personnel.router)
 base_router.include_router(base_products.router)
 base_router.include_router(base_customers.router)
+base_router.include_router(base_business_roles.router)
 v1_router.include_router(base_router)
 
 # 业务数据（需求 2.2）：/api/v1/business/*，业务操作登录即可访问
@@ -68,5 +71,7 @@ v1_router.include_router(calc_router)
 v1_router.include_router(settlements_router)
 # 报表统计（M4 ⑤）：/api/v1/reports/*，只读，限管理员/财务/领导
 v1_router.include_router(reports_router)
+# 工作台（M4 ⑧）：/api/v1/dashboard，四区块只读聚合，限管理员/财务/领导
+v1_router.include_router(dashboard_router)
 
 api_router.include_router(v1_router)