Add documentation headers across system modules

Trenser.VehicleServiceSystem/Trenser.VehicleServiceSystem/utilities/FileHelper.h

@@ -1,3 +1,12 @@
+/*
+File: FileHelper.h
+Description: Provides utility functions for loading and saving records
+             from and to CSV-like text files. Ensures files are created
+             if missing and supports simple record persistence.
+Author: Trenser
+Date: 22-May-2026
+*/
+
 #pragma once
 #include <fstream>
 #include <string>
@@ -6,6 +15,17 @@
 
 namespace util
 {
+    /*
+    Function: loadRecords
+    Description: Loads records from a given file path into a vector of strings.
+                 Skips the header line if present. Creates the file if it does not exist.
+    Parameters:
+        - filePath: const std::string&, path to the file
+    Returns:
+        - util::Vector<std::string>: Vector containing all records (excluding header)
+    Throws:
+        - None (creates file if missing)
+    */
     inline util::Vector<std::string> loadRecords(const std::string& filePath)
     {
         util::Vector<std::string> records;
@@ -30,6 +50,18 @@ namespace util
         return records;
     }
 
+    /*
+    Function: saveRecords
+    Description: Saves records to a given file path. Overwrites existing content
+                 and writes a header line followed by all records.
+    Parameters:
+        - filePath: const std::string&, path to the file
+        - records: const util::Vector<std::string>&, vector of records to save
+    Returns:
+        - void
+    Throws:
+        - std::runtime_error if the file cannot be opened for writing
+    */
     inline void saveRecords(const std::string& filePath, const util::Vector<std::string>& records)
     {
         std::ofstream file(filePath, std::ios::trunc);