Monitor service implementation

The monitor service is a simple IPC server which uses a unix socket to communicate with external rust client located at pkg/monitor. The server can send asynchronous updates about EVE status to the connected client. The information is then used by rust client to display a TUI for the user.

Client requests

Following requests are supported at the moment:

• SetDPC - sets a the current DPC with a key set to manual. It is used to apply a network configuration specified by local user through TUI. NIM service has a special handling of manual DPC
• SetServer - updates server URL in /config/server file. The request fails if the node is already onboarded.

Request/response representation

All requests and responses are sent in JSON format. Some internal EVE structures e.g. DPCList are serialized into JSON as-is and deserialized on the rust application side. It introduces a problem in case a structure is updated on EVE side, but the rust application is not updated. To avoid this problem a proxy structures should be created on EVE side in future.