fix: defer daily report push и увеличить pool БД (0.4.12)

FCM/каналы для report.daily.* после commit ingest (BackgroundTasks);
SAC_DB_POOL_SIZE=15, SAC_DB_MAX_OVERFLOW=25 для штурма 09:00.

Co-authored-by: Cursor <cursoragent@cursor.com>

backend/app/database.py

@@ -6,7 +6,11 @@ from sqlalchemy.orm import DeclarativeBase, Session, sessionmaker
 from app.config import get_settings
 
 settings = get_settings()
-engine = create_engine(settings.database_url, pool_pre_ping=True)
+_engine_kwargs: dict = {"pool_pre_ping": True}
+if settings.database_url.startswith("postgresql"):
+    _engine_kwargs["pool_size"] = max(1, int(settings.sac_db_pool_size))
+    _engine_kwargs["max_overflow"] = max(0, int(settings.sac_db_max_overflow))
+engine = create_engine(settings.database_url, **_engine_kwargs)
 SessionLocal = sessionmaker(bind=engine, autocommit=False, autoflush=False)