fix: auto-fix code issues (cron)

- 修复重复导入/字段
- 修复异常处理
- 修复PEP8格式问题
- 添加类型注解

backend/test_phase8_task5.py

@@ -525,7 +525,7 @@ class TestGrowthManager:
 
         try:
             referral = self.manager.generate_referral_code(
-                program_id=program_id, referrer_id="referrer_user_001"
+                program_id=program_id, referrer_id="referrer_user_001",
             )
 
             if referral:
@@ -551,7 +551,7 @@ class TestGrowthManager:
 
         try:
             success = self.manager.apply_referral_code(
-                referral_code=referral_code, referee_id="new_user_001"
+                referral_code=referral_code, referee_id="new_user_001",
             )
 
             if success:
@@ -579,7 +579,7 @@ class TestGrowthManager:
             assert "conversion_rate" in stats
 
             self.log(
-                f"推荐统计: {stats['total_referrals']} 推荐, {stats['conversion_rate']:.2%} 转化率"
+                f"推荐统计: {stats['total_referrals']} 推荐, {stats['conversion_rate']:.2%} 转化率",
             )
             return True
         except Exception as e:
@@ -618,7 +618,7 @@ class TestGrowthManager:
 
         try:
             incentives = self.manager.check_team_incentive_eligibility(
-                tenant_id=self.test_tenant_id, current_tier="free", team_size=5
+                tenant_id=self.test_tenant_id, current_tier="free", team_size=5,
             )
 
             self.log(f"找到 {len(incentives)} 个符合条件的激励")
@@ -642,7 +642,7 @@ class TestGrowthManager:
 
             today = dashboard["today"]
             self.log(
-                f"实时仪表板: 今日 {today['active_users']} 活跃用户, {today['total_events']} 事件"
+                f"实时仪表板: 今日 {today['active_users']} 活跃用户, {today['total_events']} 事件",
             )
             return True
         except Exception as e: