feat: 初始化 ChatGPT Team 管理机器人

核心功能:
- 实现基于 Telegram Inline Button 交互的后台面板与用户端
- 支持通过账密登录和 RT (Refresh Token) 方式添加 ChatGPT Team 账号
- 支持管理、拉取和删除待处理邀请，支持一键清空多余邀请
- 支持按剩余容量自动生成邀请兑换码，支持分页查看与一键清空未使用兑换码
- 随机邀请功能：成功拉人后自动核销兑换码
- 定时检测 Token 状态，实现自动续订/刷新并拦截封禁账号 (处理 401/402 错误)

系统与配置:
- 使用 PostgreSQL 数据库管理账号、邀请和兑换记录
- 支持在端内动态添加、移除管理员
- 完善 Docker 部署配置与 .gitignore 规则

internal/chatgpt/invite.go

@@ -0,0 +1,93 @@
+package chatgpt
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"io"
+	"log"
+	"math"
+	"net/http"
+	"strings"
+	"time"
+
+	"go-helper/internal/model"
+)
+
+const (
+	maxInviteAttempts = 3
+	retryBaseDelay    = 800 * time.Millisecond
+	retryMaxDelay     = 5 * time.Second
+)
+
+// InviteUser sends an invitation to the given email on the specified team account.
+func (c *Client) InviteUser(email string, account *model.GptAccount) error {
+	email = strings.TrimSpace(strings.ToLower(email))
+	if email == "" {
+		return fmt.Errorf("缺少邀请邮箱")
+	}
+	if account.Token == "" || account.ChatgptAccountID == "" {
+		return fmt.Errorf("账号配置不完整")
+	}
+
+	apiURL := fmt.Sprintf("https://chatgpt.com/backend-api/accounts/%s/invites", account.ChatgptAccountID)
+	payload := map[string]interface{}{
+		"email_addresses": []string{email},
+		"role":            "standard-user",
+		"resend_emails":   true,
+	}
+	bodyBytes, _ := json.Marshal(payload)
+
+	var lastErr error
+	for attempt := 1; attempt <= maxInviteAttempts; attempt++ {
+		req, err := http.NewRequest("POST", apiURL, bytes.NewReader(bodyBytes))
+		if err != nil {
+			return err
+		}
+		headers := buildHeaders(account.Token, account.ChatgptAccountID)
+		req.Header = headers
+		req.Header.Set("Content-Type", "application/json")
+		if account.OaiDeviceID != "" {
+			req.Header.Set("Oai-Device-Id", account.OaiDeviceID)
+		}
+
+		resp, err := c.httpClient.Do(req)
+		if err != nil {
+			lastErr = fmt.Errorf("网络错误: %w", err)
+			log.Printf("[Invite] 尝试 %d/%d 网络错误: %v", attempt, maxInviteAttempts, err)
+			if attempt < maxInviteAttempts {
+				sleepRetry(attempt)
+			}
+			continue
+		}
+
+		respBody, _ := io.ReadAll(resp.Body)
+		resp.Body.Close()
+
+		if resp.StatusCode >= 200 && resp.StatusCode < 300 {
+			log.Printf("[Invite] 成功邀请 %s 到账号 %s", email, account.ChatgptAccountID)
+			return nil
+		}
+
+		lastErr = fmt.Errorf("HTTP %d: %s", resp.StatusCode, truncate(string(respBody), 300))
+		log.Printf("[Invite] 尝试 %d/%d 失败: %v", attempt, maxInviteAttempts, lastErr)
+
+		if !isRetryableStatus(resp.StatusCode) || attempt >= maxInviteAttempts {
+			break
+		}
+		sleepRetry(attempt)
+	}
+	return fmt.Errorf("邀请失败（已尝试 %d 次）: %v", maxInviteAttempts, lastErr)
+}
+
+func sleepRetry(attempt int) {
+	delay := float64(retryBaseDelay) * math.Pow(2, float64(attempt-1))
+	if delay > float64(retryMaxDelay) {
+		delay = float64(retryMaxDelay)
+	}
+	time.Sleep(time.Duration(delay))
+}
+
+func isRetryableStatus(status int) bool {
+	return status == 408 || status == 429 || (status >= 500 && status <= 599)
+}