jmri: add Phase 4 TigerVNC server on :1 (port 5901) — replaces X11 forwarding

ansible/roles/jmri/templates/jmri-vnc.service.j2

@@ -0,0 +1,28 @@
+[Unit]
+Description=JMRI VNC virtual display (:{{ jmri_vnc_display }})
+After=network.target
+# Start before jmri.service so the display is ready when JMRI launches
+Before=jmri.service
+
+[Service]
+Type=simple
+User={{ jmri_user }}
+Group={{ jmri_group }}
+ExecStart=/usr/bin/Xtigervnc \
+    :{{ jmri_vnc_display }} \
+    -rfbport {{ jmri_vnc_port }} \
+    -geometry {{ jmri_vnc_geometry }} \
+    -depth {{ jmri_vnc_depth }} \
+    -SecurityTypes VncAuth \
+    -PasswordFile {{ jmri_home }}/.vnc/passwd \
+    -localhost no \
+    -AlwaysShared \
+    -NeverShared no \
+    -AcceptKeyEvents \
+    -AcceptPointerEvents \
+    -desktop "JMRI"
+Restart=on-failure
+RestartSec=5
+
+[Install]
+WantedBy=multi-user.target