Refactor logger and minor code polish

lib/modloader.dart

@@ -1,5 +1,6 @@
 import 'dart:io';
 import 'dart:async';
+import 'package:rimworld_modman/logger.dart';
 import 'package:xml/xml.dart';
 
 const root = r'C:/Users/Administrator/Seafile/Games-Rimworld';
@@ -8,75 +9,6 @@ const configRoot = '$root/AppData/RimWorld by Ludeon Studios/Config';
 const configPath = '$configRoot/ModsConfig.xml';
 const logsPath = '$root/ModManager';
 
-// Logger class for writing logs to console and file
-class Logger {
-  static final Logger _instance = Logger._internal();
-  static Logger get instance => _instance;
-
-  File? _logFile;
-  IOSink? _logSink;
-
-  Logger._internal() {
-    _initLogFile();
-  }
-
-  void _initLogFile() {
-    try {
-      // Use system temp directory
-      final tempDir = Directory.systemTemp;
-      final logFileName = 'rimworld_modman.log';
-
-      _logFile = File('${tempDir.path}${Platform.pathSeparator}$logFileName');
-      _logSink = _logFile!.openWrite(mode: FileMode.writeOnly);
-
-      info('Logging initialized. Log file: ${_logFile!.path}');
-    } catch (e) {
-      print('Failed to initialize log file: $e');
-    }
-  }
-
-  void _log(String message, String level) {
-    final timestamp = DateTime.now().toIso8601String();
-    final formattedMessage = '[$timestamp] [$level] $message';
-
-    // Always print to console
-    print(formattedMessage);
-
-    // Write to file if initialized
-    if (_logSink != null) {
-      try {
-        _logSink!.writeln(formattedMessage);
-      } catch (e) {
-        print('Error writing to log file: $e');
-      }
-    }
-  }
-
-  void info(String message) {
-    _log(message, 'INFO');
-  }
-
-  void warning(String message) {
-    _log(message, 'WARN');
-  }
-
-  void error(String message) {
-    _log(message, 'ERROR');
-  }
-
-  void close() {
-    if (_logSink != null) {
-      try {
-        _logSink!.flush();
-        _logSink!.close();
-      } catch (e) {
-        print('Error closing log file: $e');
-      }
-      _logSink = null;
-    }
-  }
-}
-
 XmlElement findCaseInsensitive(XmlElement element, String name) {
   return element.childElements.firstWhere(
     (e) => e.name.local.toLowerCase() == name,
@@ -342,7 +274,6 @@ class ModList {
 
   ModList({required this.path});
 
-  // Simplified loading with config file first
   Future<void> loadWithConfig({bool skipFileCount = false}) async {
     final logger = Logger.instance;
 
@@ -492,7 +423,7 @@ class ModList {
 
           if (loadedModsCount % 50 == 0 || loadedModsCount == totalModsFound) {
             logger.info(
-              'Progress: Loaded $loadedModsCount mods (${stopwatch.elapsedMilliseconds}ms)',
+              'Progress: Loaded $loadedModsCount mods (${modTime}ms)',
             );
           }
         } catch (e) {