Initialize narratio Go module and CLI scaffold

internal/logging/logging.go

@@ -0,0 +1,17 @@
+package logging
+
+import (
+	"io"
+	"log/slog"
+	"os"
+)
+
+// NewLogger creates a text slog logger.
+func NewLogger(out io.Writer, level slog.Level) *slog.Logger {
+	if out == nil {
+		out = os.Stderr
+	}
+
+	handler := slog.NewTextHandler(out, &slog.HandlerOptions{Level: level})
+	return slog.New(handler)
+}