Add initial setup for Central DNS and PXE services using dnsmasq

- Created README.md for Central setup documentation.
- Added dnsmasq configuration files and scripts for setting up DNS and PXE booting.
- Implemented nginx configuration to serve PXE boot assets.
- Developed setup.sh script to automate installation and configuration of dnsmasq and nginx.
- Removed outdated dnsmasq setup guide from documentation.

bin/wild-central-generate-setup

@@ -44,7 +44,7 @@ if [ -z "${WILDCLOUD_REPO}" ] || [ "${WILDCLOUD_REPO}" = "null" ]; then
 fi
 
 # The source templates for asq setup.
-DNSMASQ_TEMPLATE_DIR="${WILDCLOUD_REPO}/infrastructure_setup/dnsmasq"
+DNSMASQ_TEMPLATE_DIR="${WILDCLOUD_REPO}/central-setup/dnsmasq"
 if [ ! -d "${DNSMASQ_TEMPLATE_DIR}" ]; then
     echo "Error: DNSMasq setup directory not found at ${DNSMASQ_TEMPLATE_DIR}"
     exit 1