fix(alerts): enforce caliber rulings R1-R4 for alert generation

R1: exclude status=demo entities from alert traversal (alert_generator / deviation_engine / kpi_bep_deriver / alert_rules / cash engine)

R2: only generate alerts within the last 6 calendar months (incl. current)

R3: only regular month periods (YYYY-MM) participate

R4: decouple generation from push - empty notification_channels never blocks

Single source of truth: app/utils/alert_entity_scope.py

backend/app/api/alert_rules.py

@@ -14,6 +14,8 @@ from app.database import get_db, Base
 from app.deps import get_entity_id
 from app.auth_middleware import require_auth, require_role
 from app.models import KPIDefinition, KPIValue, KPIAlert, OperationLog
+# 裁定 R1（2026-09-19 财务口径）：demo 账套不参与预警生成/遍历（单一事实源）
+from app.utils.alert_entity_scope import is_excluded_entity
 
 logger = logging.getLogger("alert_rules")
 
@@ -257,7 +259,14 @@ def generate_default_rules(db: Session = Depends(get_db), entity_id: int = Depen
 
 @router.post("/check-all")
 def run_all_alert_checks(db: Session = Depends(get_db), entity_id: int = Depends(get_entity_id)):
-    """执行当前企业所有KPI的预警检查 — 生成新的预警记录（账套隔离 2026-08-31）"""
+    """执行当前企业所有KPI的预警检查 — 生成新的预警记录（账套隔离 2026-08-31）
+
+    R1（裁定 2026-09-19）：demo 演示账套不参与预警生成 → 直接返回 skipped。
+    """
+    if is_excluded_entity(db, entity_id):
+        logger.info("预警检查跳过（demo 账套 R1）: entity_id=%s", entity_id)
+        return {"message": f"账套 {entity_id} 为 demo 演示账套，按 R1 不参与预警生成", "generated": 0,
+                "skipped": True, "reason": "R1_demo_entity_excluded"}
     rules = db.query(AlertRule).filter(
         AlertRule.enabled == 1, AlertRule.entity_id == entity_id).all()
     kpi_cache = {}
@@ -642,7 +651,14 @@ def _check_forecast_alerts(db: Session, entity_id: int = 1) -> int:
 
 @router.post("/check-forecast")
 def run_forecast_alert_check(db: Session = Depends(get_db), entity_id: int = Depends(get_entity_id)):
-    """执行预测值预警检查 — 检查未来7天预测值是否超限（账套隔离 2026-08-31）"""
+    """执行预测值预警检查 — 检查未来7天预测值是否超限（账套隔离 2026-08-31）
+
+    R1（裁定 2026-09-19）：demo 演示账套不参与预警生成。
+    """
+    if is_excluded_entity(db, entity_id):
+        logger.info("预测值预警检查跳过（demo 账套 R1）: entity_id=%s", entity_id)
+        return {"message": f"账套 {entity_id} 为 demo 演示账套，按 R1 不参与预警生成",
+                "generated": 0, "skipped": True, "reason": "R1_demo_entity_excluded"}
     generated = _check_forecast_alerts(db, entity_id=entity_id)
     return {"message": f"预测值预警检查完成: 生成{generated}条", "generated": generated}
 
@@ -690,7 +706,14 @@ def run_forecast_deviation_check(
 ):
     """预测偏差检查（升级2b, 2026-08-25）— alert_rules type=forecast_deviation
     对每条偏差规则: 取最新预测log(kpi_forecast_log) vs 该期实际值(kpi_values)，
-    偏差 > threshold_pct → 生成/更新 pending 预警（去重）"""
+    偏差 > threshold_pct → 生成/更新 pending 预警（去重）
+
+    R1（裁定 2026-09-19）：demo 演示账套不参与预警生成。
+    """
+    if is_excluded_entity(db, entity_id):
+        logger.info("预测偏差检查跳过（demo 账套 R1）: entity_id=%s", entity_id)
+        return {"message": f"账套 {entity_id} 为 demo 演示账套，按 R1 不参与预警生成",
+                "generated": 0, "skipped": True, "reason": "R1_demo_entity_excluded"}
     from app.models import KpiForecastLog
     rules = db.query(AlertRule).filter(
         AlertRule.entity_id == entity_id,
@@ -861,7 +884,14 @@ def run_customer_concentration_check(
     entity_id: int = Depends(get_entity_id),
 ):
     """客户集中度检查（P2 2026-09-10）— 遍历本企业 customer_concentration 规则，
-    计算客户收入占比，超阈值生成/更新 pending 预警（去重）。"""
+    计算客户收入占比，超阈值生成/更新 pending 预警（去重）。
+
+    R1（裁定 2026-09-19）：demo 演示账套不参与预警生成。
+    """
+    if is_excluded_entity(db, entity_id):
+        logger.info("客户集中度检查跳过（demo 账套 R1）: entity_id=%s", entity_id)
+        return {"message": f"账套 {entity_id} 为 demo 演示账套，按 R1 不参与预警生成",
+                "generated": 0, "skipped": True, "reason": "R1_demo_entity_excluded"}
     rules = db.query(AlertRule).filter(
         AlertRule.entity_id == entity_id,
         AlertRule.rule_type == "customer_concentration",