fix(fetch-caliber): 取数层排除半年/预测伪期间 + subjects 响应补 entity_id

R3 期间口径（仅 YYYY-MM）延伸到取数层：新增 alert_entity_scope.month_period_clause()（跨库可移植 SQL 等价式），应用到 15 个文件 26 处「按 period 倒序取最新值/最近N期」位点；dashboard 原 MySQL-only REGEXP 正则收口到同单一事实源。

GET /api/cma/subjects 响应增补 entity_id（NULL=全局标准准则科目 / N=账套私有明细），既有 10 字段语义与名称不变。

证据：pending-tasks/_reports/yanxue-20260924-cma-fetch-caliber-fixes-fullstack.md（改前/改后 A/B：F_NET_PROFIT 2026-H2/-55.0 → 2026-08/-10.46）。新增 7 例回归测试；全量 1 failed(预存在) 1473 passed，基线同项。

backend/app/api/ai_analysis.py

@@ -8,6 +8,7 @@ from app.deps import get_entity_id
 from app.auth_middleware import require_auth, require_role
 from app.models import KPIDefinition, KPIValue, KPIAlert, StrategicMap, User, ActionPlan, BudgetPlan, AISuggestion
 from app.utils.cache import get as cache_get, set as cache_set
+from app.utils.alert_entity_scope import month_period_clause
 import json, hashlib, httpx, os, urllib.request, urllib.parse
 from datetime import datetime, date
 router = APIRouter(prefix="/api/cma/ai", tags=["AI分析"],
@@ -102,6 +103,7 @@ def generate_rule_suggestions(db: Session, entity_id: int,
                 KPIValue.entity_id == entity_id,
                 KPIValue.entity_id.is_(None),
             ),
+            month_period_clause(KPIValue.period),
         ).order_by(KPIValue.period.desc()).first()
         if not latest or latest.actual_value is None:
             continue
@@ -286,7 +288,9 @@ async def dashboard_analysis(role: str = Query("ceo"), db: Session = Depends(get
                                           KPIDefinition.status == "active").all()
     kpi_summary = []
     for k in kpis:
-        latest = db.query(KPIValue).filter(KPIValue.kpi_id == k.id).order_by(KPIValue.period.desc()).first()
+        latest = db.query(KPIValue).filter(
+            KPIValue.kpi_id == k.id, month_period_clause(KPIValue.period)
+        ).order_by(KPIValue.period.desc()).first()
         kpi_summary.append({
             "name": k.kpi_name,
             "code": k.kpi_code,
@@ -455,7 +459,9 @@ async def dashboard_analysis_stream(role: str = Query("ceo"), db: Session = Depe
     ).all()
     kpi_summary = []
     for k in kpis:
-        latest = db.query(KPIValue).filter(KPIValue.kpi_id == k.id).order_by(KPIValue.period.desc()).first()
+        latest = db.query(KPIValue).filter(
+            KPIValue.kpi_id == k.id, month_period_clause(KPIValue.period)
+        ).order_by(KPIValue.period.desc()).first()
         kpi_summary.append({
             "name": k.kpi_name, "code": k.kpi_code, "dimension": k.dimension,
             "target": k.target_value, "actual": latest.actual_value if latest else None,
@@ -505,7 +511,9 @@ async def ask_question(
     ).all()
     kpi_context = []
     for k in kpis:
-        latest = db.query(KPIValue).filter(KPIValue.kpi_id == k.id).order_by(KPIValue.period.desc()).first()
+        latest = db.query(KPIValue).filter(
+            KPIValue.kpi_id == k.id, month_period_clause(KPIValue.period)
+        ).order_by(KPIValue.period.desc()).first()
         alert = db.query(KPIAlert).filter(KPIAlert.kpi_id == k.id, KPIAlert.status == "pending").first()
         kpi_context.append(
             f"{k.kpi_name}({k.kpi_code}): 当前值={latest.actual_value if latest else '无'}"
@@ -573,7 +581,9 @@ async def review_plans(
     for p in plans:
         kpi = db.query(KPIDefinition).filter(KPIDefinition.id == p.kpi_id).first()
         kpi_name = kpi.kpi_name if kpi else "未知"
-        latest = db.query(KPIValue).filter(KPIValue.kpi_id == p.kpi_id).order_by(KPIValue.period.desc()).first()
+        latest = db.query(KPIValue).filter(
+            KPIValue.kpi_id == p.kpi_id, month_period_clause(KPIValue.period)
+        ).order_by(KPIValue.period.desc()).first()
         plan_text.append(
             f"- {p.title}\n"
             f"  关联KPI: {kpi_name}(当前值: {latest.actual_value if latest else '无'})\n"