feat(pay): 支付跳转功能

- 账号管理：补充订阅状态管理、TeamManager上传说明
 - 新增「支付升级」功能模块描述
 - 系统设置：补充 CPA配置和 TeamManager配置项

src/database/models.py

@@ -53,6 +53,8 @@ class Account(Base):
     cpa_uploaded = Column(Boolean, default=False)  # 是否已上传到 CPA
     cpa_uploaded_at = Column(DateTime)  # 上传时间
     source = Column(String(20), default='register')  # 'register' 或 'login'，区分账号来源
+    subscription_type = Column(String(20))  # None / 'plus' / 'team'
+    subscription_at = Column(DateTime)  # 订阅开通时间
     created_at = Column(DateTime, default=datetime.utcnow)
     updated_at = Column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)
 
@@ -74,6 +76,8 @@ class Account(Base):
             'cpa_uploaded': self.cpa_uploaded,
             'cpa_uploaded_at': self.cpa_uploaded_at.isoformat() if self.cpa_uploaded_at else None,
             'source': self.source,
+            'subscription_type': self.subscription_type,
+            'subscription_at': self.subscription_at.isoformat() if self.subscription_at else None,
             'created_at': self.created_at.isoformat() if self.created_at else None,
             'updated_at': self.updated_at.isoformat() if self.updated_at else None
         }

src/database/session.py

@@ -95,6 +95,8 @@ class DatabaseSessionManager:
             ("accounts", "cpa_uploaded", "BOOLEAN DEFAULT 0"),
             ("accounts", "cpa_uploaded_at", "DATETIME"),
             ("accounts", "source", "VARCHAR(20) DEFAULT 'register'"),
+            ("accounts", "subscription_type", "VARCHAR(20)"),
+            ("accounts", "subscription_at", "DATETIME"),
         ]
 
         with self.engine.connect() as conn: