feat: initialize Go agent module with config, Makefile and project structure

Agent/Makefile

@@ -0,0 +1,17 @@
+.PHONY: build build-windows build-linux clean
+
+BINARY=nexus-agent
+VERSION=$(shell git describe --tags --always --dirty 2>/dev/null || echo "dev")
+LDFLAGS=-ldflags "-s -w -X main.version=$(VERSION)"
+
+build:
+	go build $(LDFLAGS) -o bin/$(BINARY) ./cmd/agent
+
+build-windows:
+	GOOS=windows GOARCH=amd64 go build $(LDFLAGS) -o bin/$(BINARY).exe ./cmd/agent
+
+build-linux:
+	GOOS=linux GOARCH=amd64 go build $(LDFLAGS) -o bin/$(BINARY)-linux ./cmd/agent
+
+clean:
+	rm -rf bin/

Agent/cmd/agent/main.go

@@ -0,0 +1,9 @@
+package main
+
+import "fmt"
+
+var version = "dev"
+
+func main() {
+	fmt.Printf("NexusRMM Agent %s\n", version)
+}

Agent/go.mod

@@ -0,0 +1,24 @@
+module github.com/nexusrmm/agent
+
+go 1.22
+
+require (
+	github.com/shirou/gopsutil/v4 v4.24.0
+	google.golang.org/grpc v1.60.0
+	google.golang.org/protobuf v1.32.0
+	gopkg.in/yaml.v3 v3.0.1
+)
+
+require (
+	github.com/ebitengine/purego v0.7.0 // indirect
+	github.com/golang/protobuf v1.5.3 // indirect
+	github.com/lufia/plan9stats v0.0.0-20240513124658-fba389f38bae // indirect
+	github.com/power-devops/perfstat v0.0.0-20240221224432-82ca36839d84 // indirect
+	github.com/tklauser/go-sysconf v0.3.14 // indirect
+	github.com/tklauser/numcpus v0.8.0 // indirect
+	github.com/yusufpapurcu/info v0.0.0-20240514213526-8f62d0eb11ac // indirect
+	golang.org/x/net v0.21.0 // indirect
+	golang.org/x/sys v0.17.0 // indirect
+	golang.org/x/text v0.14.0 // indirect
+	google.golang.org/genproto/googleapis/rpc v0.0.0-20240221002015-b0ce06bbee7c // indirect
+)

Agent/internal/config/config.go

@@ -0,0 +1,40 @@
+package config
+
+import (
+	"os"
+
+	"gopkg.in/yaml.v3"
+)
+
+type Config struct {
+	ServerAddress     string `yaml:"server_address"`
+	AgentID           string `yaml:"agent_id"`
+	HeartbeatInterval int    `yaml:"heartbeat_interval"`
+	TLSEnabled        bool   `yaml:"tls_enabled"`
+}
+
+func Load(path string) (*Config, error) {
+	cfg := &Config{
+		ServerAddress:     "localhost:5001",
+		HeartbeatInterval: 60,
+	}
+	data, err := os.ReadFile(path)
+	if err != nil {
+		if os.IsNotExist(err) {
+			return cfg, nil
+		}
+		return nil, err
+	}
+	if err := yaml.Unmarshal(data, cfg); err != nil {
+		return nil, err
+	}
+	return cfg, nil
+}
+
+func (c *Config) Save(path string) error {
+	data, err := yaml.Marshal(c)
+	if err != nil {
+		return err
+	}
+	return os.WriteFile(path, data, 0600)
+}