Add custom QZ Tray fork with pairing key authentication

- Custom fork of QZ Tray 2.2.x with certificate validation bypassed
- Implemented pairing key (HMAC) authentication as replacement
- Modified files: PrintSocketClient.java (certificate check disabled)
- New files: PairingAuth.java, PairingConfigDialog.java
- Excluded build artifacts (out/, lib/javafx*) from repository
- Library JARs included for dependency management

tray/assets/pgl_sample.txt

@@ -0,0 +1,12 @@
+~CREATE;DATAMATRIX;144
+SCALE;DOT;300;300
+ALPHA
+POINT;50;100;16;9;*Printed using QZ Tray*
+STOP
+BARCODE
+DATAMATRIX;XD16;C20;R20;ECC200;ID5;150;150
+*0100000123000017*
+STOP
+END
+~EXECUTE;DATAMATRIX;1
+~NORMAL