feat: 添加启动任务开关，修复统计聚合内存泄漏

- 新增 CACHE_WARMUP_ENABLED 和 MAINTENANCE_STARTUP_TASKS_ENABLED 环境变量，
  允许禁用缓存预热和维护调度器启动任务
- 在统计聚合批量处理循环中添加 db.expunge_all()，释放 Session identity map，
  防止 ORM 对象累积导致内存暴涨
- 添加启动任务开关的单元测试

src/config/settings.py

@@ -312,6 +312,14 @@ class Config:
         # 每个用户最多可创建的 Management Token 数量
         self.management_token_max_per_user = int(os.getenv("MANAGEMENT_TOKEN_MAX_PER_USER", "20"))
 
+        # 启动任务开关
+        # CACHE_WARMUP_ENABLED: 是否在启动时执行缓存预热
+        # MAINTENANCE_STARTUP_TASKS_ENABLED: 是否在启动时执行维护调度器初始化任务（清理、统计回填等）
+        self.cache_warmup_enabled = os.getenv("CACHE_WARMUP_ENABLED", "true").lower() == "true"
+        self.maintenance_startup_tasks_enabled = (
+            os.getenv("MAINTENANCE_STARTUP_TASKS_ENABLED", "true").lower() == "true"
+        )
+
         # API 文档配置
         # DOCS_ENABLED: 是否启用 API 文档（/docs, /redoc, /openapi.json）
         #   - 未设置: 开发环境启用，生产环境禁用

src/services/system/cache_warmup.py

@@ -17,6 +17,7 @@ from typing import Any
 
 from sqlalchemy.orm import Session
 
+from src.config.settings import config
 from src.core.enums import UserRole
 from src.core.logger import logger
 from src.database import create_session
@@ -172,4 +173,8 @@ class CacheWarmupService:
 
 async def start_cache_warmup() -> None:
     """启动缓存预热（作为后台任务）"""
+    if not config.cache_warmup_enabled:
+        logger.info("缓存预热已禁用（CACHE_WARMUP_ENABLED=false）")
+        return
+
     asyncio.create_task(CacheWarmupService.warmup_all())

src/services/system/maintenance_scheduler.py

@@ -23,6 +23,7 @@ from typing import Any
 
 from sqlalchemy import delete, literal_column, text
 
+from src.config.settings import config
 from src.core.logger import logger
 from src.database import create_session
 from src.models.database import AuditLog, Provider, RequestCandidate, Usage
@@ -232,7 +233,10 @@ class MaintenanceScheduler:
         )
 
         # 启动时执行一次初始化任务
-        asyncio.create_task(self._run_startup_tasks())
+        if config.maintenance_startup_tasks_enabled:
+            asyncio.create_task(self._run_startup_tasks())
+        else:
+            logger.info("维护调度器启动任务已禁用（MAINTENANCE_STARTUP_TASKS_ENABLED=false）")
 
     async def _run_startup_tasks(self) -> None:
         """启动时执行的初始化任务"""
@@ -470,6 +474,7 @@ class MaintenanceScheduler:
                                 StatsAggregatorService.aggregate_daily_stats_bundle(
                                     db, current_date_utc, user_ids=user_ids
                                 )
+                                db.expunge_all()
                             except Exception as e:
                                 failed_dates += 1
                                 logger.warning(f"回填日期 {current_date} 失败: {e}")

src/services/system/stats_aggregator.py

@@ -1096,6 +1096,7 @@ class StatsAggregatorService:
         current_date = start_date
         while current_date < today_utc:
             StatsAggregatorService.aggregate_daily_stats_bundle(db, current_date, user_ids=user_ids)
+            db.expunge_all()  # 释放 Session identity map，防止 ORM 对象累积导致内存暴涨
             count += 1
             current_date += timedelta(days=1)
 
@@ -1114,6 +1115,7 @@ class StatsAggregatorService:
         count = 0
         while current <= end_dt:
             StatsAggregatorService.aggregate_daily_api_key_stats(db, current, commit=True)
+            db.expunge_all()
             count += 1
             current += timedelta(days=1)
         return count
@@ -1145,9 +1147,11 @@ class StatsAggregatorService:
                 processed += 1
             if processed % 30 == 0:
                 db.commit()
+                db.expunge_all()
             current += timedelta(days=1)
 
         db.commit()
+        db.expunge_all()
         return processed
 
     @staticmethod
@@ -1183,6 +1187,7 @@ class StatsAggregatorService:
             db.commit()
             last_id = records[-1].id
             total_processed += len(records)
+            db.expunge_all()
 
         return total_processed
 
@@ -1194,6 +1199,7 @@ class StatsAggregatorService:
         count = 0
         while current <= end_dt:
             StatsAggregatorService.aggregate_daily_error_stats(db, current, commit=True)
+            db.expunge_all()
             count += 1
             current += timedelta(days=1)
         return count