add method to handlers

kontor-gin/internal/api/file.go

@@ -0,0 +1,22 @@
+package api
+
+import (
+	"encoding/json"
+	"log/slog"
+	"os"
+)
+
+func WriteJson(data *ExportData, fileName string) error {
+	jsonData, err := json.MarshalIndent(data, "", "    ")
+	if err != nil {
+		slog.Info("JSON MarshalIndent failed", "Error:", err)
+		return err
+	}
+	// Write bytes to file
+	err = os.WriteFile(fileName, jsonData, 0644)
+	if err != nil {
+		slog.Info("Error writing file:", "Error", err)
+		return err
+	}
+	return nil
+}