Integrate NLog for centralized logging, replacing Console calls across CLI tasks. Add LoggingService helper for setup and logger retrieval. Update project dependencies.

Cli/Helper/LoggingService.cs

@@ -0,0 +1,56 @@
+using NLog;
+using NLog.Config;
+using NLog.Targets;
+
+namespace FsToolbox.Cli.Helper
+{
+    /// <summary>
+    ///     Central logging setup using NLog with console and file targets.
+    /// </summary>
+    public static class LoggingService
+    {
+        private static bool _initialized;
+
+        /// <summary>
+        ///     Configures NLog with console and rolling file targets.
+        /// </summary>
+        public static void Initialize()
+        {
+            if (_initialized) return;
+
+            var config = new LoggingConfiguration();
+            var layout = "${longdate} | ${uppercase:${level}} | ${logger} | ${message}${onexception:inner=${newline}${exception:format=tostring}}";
+
+            var consoleTarget = new ConsoleTarget("console")
+            {
+                Layout = layout
+            };
+
+            var fileTarget = new FileTarget("file")
+            {
+                FileName = "${basedir}/logs/fstool.log",
+                ArchiveEvery = FileArchivePeriod.Day,
+                ArchiveNumbering = ArchiveNumberingMode.Rolling,
+                MaxArchiveFiles = 7,
+                Layout = layout,
+                CreateDirs = true
+            };
+
+            config.AddRule(LogLevel.Info, LogLevel.Fatal, consoleTarget);
+            config.AddRule(LogLevel.Info, LogLevel.Fatal, fileTarget);
+
+            LogManager.Configuration = config;
+            _initialized = true;
+        }
+
+        /// <summary>
+        ///     Gets a logger for the specified type.
+        /// </summary>
+        public static Logger GetLogger<T>() => LogManager.GetLogger(typeof(T).FullName);
+
+        /// <summary>
+        ///     Gets a logger for the specified name.
+        /// </summary>
+        public static Logger GetLogger(string name) => LogManager.GetLogger(name);
+    }
+}