Retrieves the full deployment configuration for a specified EdgeConnect appliance. This is the first step of the read-modify-write workflow for changing any deployment setting (interfaces, DHCP, routing, etc.). When cached is true, returns data from Orchestrator's database (faster, may be stale). When cached is false, fetches live data directly from the appliance (slower, always current). Use cached=false when retrieving a config you intend to modify. To apply changes after modifying the returned object, POST the full modified deployment JSON to POST /appliance/rest?nePk={nePk}&url=deployment (see the 'appliance' tag). Key data paths: Interface configs are in modeIfs[].applianceIPs[]. DHCP server config (including DNS servers) is at modeIfs[].applianceIPs[].dhcpd.server.dns. Interface label/zone/vrf fields are numeric IDs — resolve to names via sysConfig.ifLabels, sysConfig.zones, and sysConfig.vrfs. Requires 'read' or 'read-write' role.