fix: keep panel restarts from hanging on the CPU job and Telegram (#7029)

Restarting the panel left it unreachable for up to a minute. CheckCpuJob sampled cpu.Percent over its whole one-minute period, so cron.Stop nearly always waited on it; it now diffs cpu.Times against its previous run (iowait counted as idle, as before). With Telegram unreachable, bus.Stop waited on an in-flight send and tgbot.Start ran getMe/setMyCommands inline; each bot call now returns once StopBot closes the bot's stop channel, the bot stops before the bus, and the artwork/commands warm-up runs in the background.

internal/web/job/check_cpu_usage.go

@@ -1,25 +1,38 @@
 package job
 
 import (
-	"time"
-
 	"github.com/mhsanaei/3x-ui/v3/internal/eventbus"
+	"github.com/mhsanaei/3x-ui/v3/internal/util/sys"
 
 	"github.com/shirou/gopsutil/v4/cpu"
 )
 
 // CheckCpuJob monitors CPU usage and publishes events when threshold is exceeded.
-type CheckCpuJob struct{}
+type CheckCpuJob struct {
+	readTimes func(percpu bool) ([]cpu.TimesStat, error)
+	last      cpu.TimesStat
+	hasLast   bool
+}
 
 // NewCheckCpuJob creates a new CPU monitoring job instance.
 func NewCheckCpuJob() *CheckCpuJob {
-	return new(CheckCpuJob)
+	return &CheckCpuJob{readTimes: cpu.Times}
 }
 
-// Run checks CPU usage and publishes a cpu.high event with raw metric data.
+// Run publishes a cpu.high event with the CPU usage since the previous run. It
+// must not sample in place: cron.Stop, and so every panel restart, waits on it.
 func (j *CheckCpuJob) Run() {
-	percent, err := cpu.Percent(1*time.Minute, false)
-	if err != nil || len(percent) == 0 {
+	times, err := j.readTimes(false)
+	if err != nil || len(times) == 0 {
+		return
+	}
+	prev, hadPrev := j.last, j.hasLast
+	j.last, j.hasLast = times[0], true
+	if !hadPrev {
+		return
+	}
+	percent, ok := sys.CPUWorkPercent(prev, times[0])
+	if !ok {
 		return
 	}
 
@@ -27,7 +40,7 @@ func (j *CheckCpuJob) Run() {
 		EventBus.Publish(eventbus.Event{
 			Type: eventbus.EventCPUHigh,
 			Data: &eventbus.SystemMetricData{
-				Percent: percent[0],
+				Percent: percent,
 			},
 		})
 	}