feat: initialize golang project template with docker and ci/cd

cmd/app/main.go

@@ -0,0 +1,51 @@
+package main
+
+import (
+	"context"
+	"log/slog"
+	"os"
+	"os/signal"
+	"syscall"
+	"time"
+)
+
+func main() {
+	logger := slog.New(slog.NewJSONHandler(os.Stdout, nil))
+	slog.SetDefault(logger)
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	// Handle OS signals
+	go func() {
+		sigChan := make(chan os.Signal, 1)
+		signal.Notify(sigChan, syscall.SIGINT, syscall.SIGTERM)
+		<-sigChan
+		slog.Info("Received shutdown signal")
+		cancel()
+	}()
+
+	if err := run(ctx); err != nil {
+		slog.Error("Application error", "error", err)
+		os.Exit(1)
+	}
+}
+
+func run(ctx context.Context) error {
+	slog.Info("Starting application...")
+
+	// Simulate long running process or server start
+	// e.g. server.ListenAndServe()
+
+	<-ctx.Done()
+	slog.Info("Shutting down application...")
+	
+	// Cleanup with timeout
+	_, shutdownCancel := context.WithTimeout(context.Background(), 5*time.Second)
+	defer shutdownCancel()
+
+	// Pretend to cleanup
+	time.Sleep(100 * time.Millisecond)
+	
+	return nil
+}