perf: prevent cron job overlap, auto-set GOMEMLIMIT, fix tgbot userStates race

cron: SkipIfStillRunning stops a slow 5s/10s job from overlapping itself and racing the shared xrayAPI (grpc conn leak) and the StatsLastValues map (fatal concurrent map write). memlimit: auto-detect a Go soft memory limit from XUI_MEMORY_LIMIT, the cgroup limit, or system RAM (about 90 percent); opt-in pprof via XUI_PPROF. tgbot: userStates now goes through a mutex-guarded store with TTL pruning (was raced by worker-pool and delayed-delete goroutines). check_client_ip: prefilter inbounds by settings LIKE limitIp instead of loading and JSON-parsing all of them every scan. minor: prune StatsLastValues, RateLimiter.lastSent, reportedRemoteTagConflict. docker-compose: document the memory knobs.

internal/web/job/check_client_ip_job.go

@@ -157,7 +157,7 @@ func (j *CheckClientIpJob) hasLimitIp() bool {
 	db := database.GetDB()
 	var inbounds []*model.Inbound
 
-	err := db.Model(model.Inbound{}).Find(&inbounds).Error
+	err := db.Model(model.Inbound{}).Where("settings LIKE ?", "%limitIp%").Find(&inbounds).Error
 	if err != nil {
 		return false
 	}