perf: 优化 MySQL 查询并接入 pytest

web/backend/routers/dashboard.py

@@ -55,9 +55,14 @@ def dashboard_summary(
     """返回首页所需的全部轻量统计。"""
     douyu_accounts = 0
     if user_has_permission(current, "account:view_all"):
-        douyu_accounts = db.query(Account).count()
+        douyu_accounts = db.query(func.count(Account.id)).scalar() or 0
     elif user_has_permission(current, "account:view_assigned"):
-        douyu_accounts = db.query(Account).filter(Account.assigned_to == current.id).count()
+        douyu_accounts = (
+            db.query(func.count(Account.id))
+            .filter(Account.assigned_to == current.id)
+            .scalar()
+            or 0
+        )
 
     login_tasks = _empty_task_summary()
     if any(user_has_permission(current, permission) for permission in (
@@ -79,7 +84,7 @@ def dashboard_summary(
         )
         if not user_has_permission(current, "login:view_all"):
             cookie_query = cookie_query.filter(Account.assigned_to == current.id)
-        cookies = cookie_query.count()
+        cookies = cookie_query.with_entities(func.count(LoginTask.id)).scalar() or 0
 
     huya_accounts = 0
     can_view_huya_accounts = any(user_has_permission(current, permission) for permission in (
@@ -91,7 +96,7 @@ def dashboard_summary(
         huya_account_query = db.query(HuyaAccount)
         if not _can_view_huya_all(current):
             huya_account_query = huya_account_query.filter(HuyaAccount.assigned_to == current.id)
-        huya_accounts = huya_account_query.count()
+        huya_accounts = huya_account_query.with_entities(func.count(HuyaAccount.id)).scalar() or 0
 
     huya_tasks = _empty_task_summary()
     huya_goods = 0
@@ -101,8 +106,8 @@ def dashboard_summary(
         if not _can_view_huya_all(current):
             huya_task_query = huya_task_query.filter(HuyaAccount.assigned_to == current.id)
         huya_tasks = _task_summary(huya_task_query, HuyaTask)
-        huya_goods = db.query(HuyaGoodsSnapshot).count()
-        huya_recharge_goods = db.query(HuyaRechargeGoodsSnapshot).count()
+        huya_goods = db.query(func.count(HuyaGoodsSnapshot.id)).scalar() or 0
+        huya_recharge_goods = db.query(func.count(HuyaRechargeGoodsSnapshot.id)).scalar() or 0
 
     return {
         "douyu": {