use xz for server topic compression

[532910]

1. xz has higher compression ratio than zip
2. xz procession is simpler and native on the linux (server side)

[heX16]

Compression is not described in the standard MQTT 3.1.1.
If you need to transfer volume data then use another protocol, for example HTTP with enabled GZ compression.

[532910]

What are you talking about?
server topic is zip compressed.

[532910]

linear-mqtt-dashboard/app/src/main/java/com/ravendmaster/linearmqttdashboard/service/MQTTService.java

Line 424 in 8654875

ZipOutputStream os = new ZipOutputStream(new BufferedOutputStream(bo));