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/scheduler/scheduler.go

@@ -0,0 +1,96 @@
+package scheduler
+
+import (
+	"log"
+	"strings"
+	"time"
+
+	"go-helper/internal/chatgpt"
+	"go-helper/internal/database"
+)
+
+// StartTokenChecker runs a periodic loop that refreshes access tokens
+// for all accounts that have a refresh token.
+func StartTokenChecker(db *database.DB, client *chatgpt.Client, intervalMinutes int) {
+	if intervalMinutes <= 0 {
+		intervalMinutes = 30
+	}
+	interval := time.Duration(intervalMinutes) * time.Minute
+	log.Printf("[Scheduler] Token 定时检测已启动，间隔 %d 分钟", intervalMinutes)
+
+	go func() {
+		// Run once immediately at startup.
+		checkAndRefreshAll(db, client)
+
+		ticker := time.NewTicker(interval)
+		defer ticker.Stop()
+		for range ticker.C {
+			checkAndRefreshAll(db, client)
+		}
+	}()
+}
+
+func checkAndRefreshAll(db *database.DB, client *chatgpt.Client) {
+	accounts, err := db.GetAccountsWithRT()
+	if err != nil {
+		log.Printf("[Scheduler] 获取账号列表失败: %v", err)
+		return
+	}
+
+	if len(accounts) == 0 {
+		return
+	}
+
+	log.Printf("[Scheduler] 开始检查 %d 个账号的 Token 状态", len(accounts))
+
+	refreshed, failed, banned := 0, 0, 0
+	for _, acc := range accounts {
+		result, err := client.RefreshAccessToken(acc.RefreshToken)
+		if err != nil {
+			log.Printf("[Scheduler] 刷新失败 [ID=%d %s]: %v", acc.ID, acc.Email, err)
+			failed++
+
+			// Check if the error indicates token is completely invalid.
+			errMsg := strings.ToLower(err.Error())
+			if strings.Contains(errMsg, "invalid_grant") ||
+				strings.Contains(errMsg, "token has been revoked") ||
+				strings.Contains(errMsg, "unauthorized") {
+				log.Printf("[Scheduler] RT 无效，标记封号 [ID=%d %s]", acc.ID, acc.Email)
+				_ = db.BanAccount(acc.ID)
+				banned++
+			}
+			continue
+		}
+
+		if err := db.UpdateAccountTokens(acc.ID, result.AccessToken, result.RefreshToken); err != nil {
+			log.Printf("[Scheduler] 更新 Token 失败 [ID=%d]: %v", acc.ID, err)
+			failed++
+			continue
+		}
+
+		// Also try to fetch account info to update subscription expiry.
+		infos, err := client.FetchAccountInfo(result.AccessToken)
+		if err != nil {
+			// Token works but account info fetch failed — might be account_deactivated.
+			errMsg := strings.ToLower(err.Error())
+			if strings.Contains(errMsg, "account_deactivated") || strings.Contains(errMsg, "已停用") {
+				log.Printf("[Scheduler] 账号已停用，标记封号 [ID=%d %s]", acc.ID, acc.Email)
+				_ = db.BanAccount(acc.ID)
+				banned++
+				continue
+			}
+		} else if len(infos) > 0 {
+			// Update expire_at from subscription info.
+			for _, info := range infos {
+				if info.AccountID == acc.ChatgptAccountID && info.ExpiresAt != "" {
+					_ = db.UpdateAccountInfo(acc.ID, acc.ChatgptAccountID, info.ExpiresAt)
+					break
+				}
+			}
+		}
+
+		refreshed++
+	}
+
+	log.Printf("[Scheduler] 检查完成: 刷新成功 %d, 失败 %d, 封号 %d", refreshed, failed, banned)
+}