Refactor logger and minor code polish

lib/logger.dart

@@ -0,0 +1,70 @@
+import 'dart:io';
+
+// 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;
+    }
+  }
+}