feat: add initial project structure with logging and watchdog service

Implement basic watchdog service for Linux systemd with:
- Configuration loading
- Logging system with database support
- WebSocket log broadcasting
- TCP server for agent communication
- Project setup with Go modules

main.go

@@ -0,0 +1,78 @@
+package main
+
+import (
+	"Watchdog_Linux-systemd/postLog"
+	"fmt"
+	"net"
+)
+
+const (
+	listenAddr = "127.0.0.1"
+	listenPort = "10080"
+	Type       = "tcp"
+)
+
+type SoftwareInfo struct {
+	Name        string
+	Version     string
+	Developer   string
+	BuildVer    int16
+	Description string
+	BuildType   string
+}
+
+var softwareInfo SoftwareInfo = SoftwareInfo{
+	Name:        "Watchdog_Linux-systemd",
+	Version:     "0.0.1",
+	Developer:   "Super-frpc",
+	BuildVer:    1,
+	Description: "Super-frpc Watchdog service for Linux systemd",
+	BuildType:   "Debug",
+}
+
+var isDebug bool
+
+func main() {
+	loadConfig()
+	if isDebug == true {
+		postLog.SetDebugMode(true)
+	}
+	postLog.Info(fmt.Sprintf("%s %s (Build %d.%s) by %s", softwareInfo.Name, softwareInfo.Version, softwareInfo.BuildVer, softwareInfo.BuildType, softwareInfo.Developer))
+	listen, err := net.Listen(Type, fmt.Sprintf("%s:%s", listenAddr, listenPort))
+	if err != nil {
+		postLog.Fatal(fmt.Sprintf("Failed to listen: %v, err: %v, %v", listenAddr, listenPort, err))
+	}
+	defer listen.Close()
+	postLog.Info(fmt.Sprintf("Server is running on %s:%s", listenAddr, listenPort))
+
+	for {
+		conn, err := listen.Accept()
+		if err != nil {
+			postLog.Error(fmt.Sprintf("Failed to accept: %v, err: %v", conn, err))
+		}
+		go handleRequest(conn)
+	}
+}
+
+func handleRequest(conn net.Conn) {
+	defer conn.Close()
+
+	buffer := make([]byte, 1024)
+	n, err := conn.Read(buffer)
+	if err != nil {
+		postLog.Error(fmt.Sprintf("Failed to read: %v, err: %v", conn, err))
+		return
+	}
+
+	recvMsg := string(buffer[:n])
+	postLog.Debug(fmt.Sprintf("Received: %v", recvMsg))
+	responseMsg := ""
+	if recvMsg == "watchdogAgentConnectionTest" {
+		responseMsg = "success"
+	} else {
+		responseMsg = "error: unknown message"
+	}
+	if _, err := conn.Write([]byte(responseMsg)); err != nil {
+		postLog.Error(fmt.Sprintf("Failed to write: %v, err: %v", conn, err))
+	}
+}