zinit: stabilize ntp/network/getty runtime

• ntp: robust /etc/ntp.conf symlink, safe defaults, avoid nounset, keep BusyBox CLI -p usage

• network: wrap dhcpcd to create dhcpcd user/group if missing; run as root if needed

• console: set getty console to 115200 vt100

config/zinit/gettyconsole.yaml

@@ -1,2 +1,2 @@
-exec: /sbin/getty console
-restart: always
+exec: /sbin/getty -L 115200 console vt100
+restart: always