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/eventbus/filter.go

@@ -7,9 +7,10 @@ import (
 
 // RateLimiter prevents notification spam from flapping events.
 type RateLimiter struct {
-	mu       sync.Mutex
-	lastSent map[string]time.Time
-	cooldown time.Duration
+	mu        sync.Mutex
+	lastSent  map[string]time.Time
+	cooldown  time.Duration
+	lastPrune time.Time
 }
 
 // NewRateLimiter creates a rate limiter with the given cooldown period.
@@ -23,11 +24,29 @@ func NewRateLimiter(cooldown time.Duration) *RateLimiter {
 // Allow returns true if the event should be sent (cooldown has elapsed).
 func (r *RateLimiter) Allow(eventType EventType, source string) bool {
 	key := string(eventType) + ":" + source
+	now := time.Now()
 	r.mu.Lock()
 	defer r.mu.Unlock()
-	if time.Since(r.lastSent[key]) < r.cooldown {
+	r.pruneLocked(now)
+	if now.Sub(r.lastSent[key]) < r.cooldown {
 		return false
 	}
-	r.lastSent[key] = time.Now()
+	r.lastSent[key] = now
 	return true
 }
+
+// pruneLocked drops keys whose cooldown has elapsed. Such an entry no longer
+// affects Allow's result, so removing it is safe and keeps the map from
+// retaining one entry per (eventType, source) ever seen. Throttled to once per
+// cooldown so a busy bus doesn't sweep the whole map on every event.
+func (r *RateLimiter) pruneLocked(now time.Time) {
+	if now.Sub(r.lastPrune) < r.cooldown {
+		return
+	}
+	r.lastPrune = now
+	for k, v := range r.lastSent {
+		if now.Sub(v) >= r.cooldown {
+			delete(r.lastSent, k)
+		}
+	}
+}