feat: Implement core backend infrastructure including configuration management, SQLite database with team owners and app settings, and initial owner-related APIs and frontend components.

backend/internal/invite/team.go

@@ -36,6 +36,14 @@ type AccountCheckResponse struct {
 	} `json:"accounts"`
 }
 
+// AccountStatus 账户状态检查结果
+type AccountStatus struct {
+	Status    string // active, banned, token_expired, error
+	PlanType  string // team, plus, free 等
+	AccountID string // 账户 ID
+	Error     string // 错误信息
+}
+
 // New 创建邀请器 (使用默认代理)
 func New(accessToken string) *TeamInviter {
 	c, _ := client.New(DefaultProxy)
@@ -59,6 +67,77 @@ func (t *TeamInviter) SetAccountID(accountID string) {
 	t.accountID = accountID
 }
 
+// CheckAccountStatus 检查账户状态（封禁检测）
+// 基于 check_ban.py 的逻辑:
+// - HTTP 200 + 有账户数据 → active
+// - HTTP 200 + 无账户数据 → banned
+// - HTTP 401 → token_expired
+// - HTTP 403 → banned
+func (t *TeamInviter) CheckAccountStatus() AccountStatus {
+	result := AccountStatus{Status: "error"}
+
+	req, _ := http.NewRequest("GET", "https://chatgpt.com/backend-api/accounts/check/v4-2023-04-27", nil)
+	req.Header.Set("Authorization", "Bearer "+t.accessToken)
+	req.Header.Set("Accept", "application/json")
+	req.Header.Set("User-Agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/131.0.0.0 Safari/537.36")
+
+	resp, err := t.client.Do(req)
+	if err != nil {
+		result.Error = fmt.Sprintf("请求失败: %v", err)
+		return result
+	}
+	defer resp.Body.Close()
+
+	body, _ := io.ReadAll(resp.Body)
+
+	switch resp.StatusCode {
+	case 200:
+		var checkResp AccountCheckResponse
+		if err := json.Unmarshal(body, &checkResp); err != nil {
+			result.Error = fmt.Sprintf("解析失败: %v", err)
+			return result
+		}
+
+		// 检查是否有账户数据
+		if len(checkResp.Accounts) == 0 {
+			result.Status = "banned"
+			result.Error = "无账户数据"
+			return result
+		}
+
+		// 查找非 default 的账户
+		for accountID, info := range checkResp.Accounts {
+			if accountID == "default" {
+				continue
+			}
+			result.Status = "active"
+			result.AccountID = accountID
+			result.PlanType = info.Account.PlanType
+			t.accountID = accountID
+			return result
+		}
+
+		// 只有 default 账户，也视为正常
+		result.Status = "active"
+		result.PlanType = "default"
+		return result
+
+	case 401:
+		result.Status = "token_expired"
+		result.Error = "Token 已过期"
+		return result
+
+	case 403:
+		result.Status = "banned"
+		result.Error = "账户被封禁 (403)"
+		return result
+
+	default:
+		result.Error = fmt.Sprintf("HTTP %d", resp.StatusCode)
+		return result
+	}
+}
+
 // GetAccountID 获取 Team 的 account_id (workspace_id)
 func (t *TeamInviter) GetAccountID() (string, error) {
 	req, _ := http.NewRequest("GET", "https://chatgpt.com/backend-api/accounts/check/v4-2023-04-27", nil)