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/web.go

@@ -814,6 +814,10 @@ func (s *Server) stop(stopXray bool, stopTgBot bool) error {
 			err2 = common.Combine(err2, err)
 		}
 	}
+	// Before the bus: its Telegram notifier may sit in a send only StopBot ends.
+	if stopTgBot && s.tgbotService.IsRunning() {
+		s.tgbotService.Stop()
+	}
 	if s.bus != nil {
 		s.bus.Stop()
 	}
@@ -823,9 +827,6 @@ func (s *Server) stop(stopXray bool, stopTgBot bool) error {
 	if stopXray {
 		service.StopTrafficWriter()
 	}
-	if stopTgBot && s.tgbotService.IsRunning() {
-		s.tgbotService.Stop()
-	}
 	if s.discordGateway != nil && s.discordGateway.IsRunning() {
 		s.discordGateway.Stop()
 	}