feat: 配置列表分页与钉钉机器人分钟级排队限流

统一 sources/templates/channels/rules 列表为分页响应，避免配置增多时全量返回；按钉钉 access_token 限制每分钟发送并在超限时等待下一分钟，降低触发官方封禁风险。

Co-authored-by: Cursor <cursoragent@cursor.com>

cmd/server/main.go

@@ -105,9 +105,19 @@ func main() {
 	matcher := engine.NewMatcher(st, redisCache)
 	renderer := engine.NewRenderer()
 
+	// DingTalk per-robot rate limit (queue/wait when over 18/min by default)
+	var dingtalkLimiter *adapter.DingTalkLimiter
+	limitPerMin := cfg.RateLimit.DingTalkPerMin
+	if redisCache != nil {
+		dingtalkLimiter = adapter.NewDingTalkLimiter(redisCache, limitPerMin)
+	} else {
+		dingtalkLimiter = adapter.NewMemoryDingTalkLimiter(limitPerMin)
+		slog.Warn("dingtalk rate limit using in-memory store (single instance only)")
+	}
+
 	// Build sender factory
 	senderFactory := func(channelType string) (adapter.ChannelSender, error) {
-		return adapter.NewSender(channelType, &cfg.SMTP)
+		return adapter.NewSender(channelType, &cfg.SMTP, dingtalkLimiter)
 	}
 	router := engine.NewRouter(st, redisCache, senderFactory)