Add Windows local node launch logs

lib/services/app_paths.dart

@@ -47,6 +47,14 @@ class AppPaths {
     return File(p.join((await appSupportDir()).path, 'peyad.pid'));
   }
 
+  static Future<File> localNodeLogFile() async {
+    return File(p.join((await appSupportDir()).path, 'peyad.log'));
+  }
+
+  static Future<File> localNodeLauncherLogFile() async {
+    return File(p.join((await appSupportDir()).path, 'peyad-launcher.log'));
+  }
+
   static Future<List<File>> legacyConfigFiles() async {
     final targetRoot = Directory(_targetAppSupportPath());
     final legacyRoot = Directory(_legacyAppSupportPath());

lib/services/windows_local_node_service.dart

@@ -1,4 +1,5 @@
 import 'dart:async';
+import 'dart:convert';
 import 'dart:io';
 
 import 'package:logger/logger.dart';
@@ -86,6 +87,10 @@ class WindowsLocalNodeService implements LocalNodeService {
       return false;
     }
     final pidFile = await _pidFilePath();
+    final daemonLogFile = await AppPaths.localNodeLogFile();
+    final launcherLogFile = await AppPaths.localNodeLauncherLogFile();
+    await launcherLogFile.parent.create(recursive: true);
+    final workingDirectory = p.dirname(binary);
     final args = <String>[
       '--non-interactive',
       '--rpc-bind-ip',
@@ -94,15 +99,30 @@ class WindowsLocalNodeService implements LocalNodeService {
       config.rpcPort.toString(),
       '--pidfile',
       pidFile,
+      '--log-file',
+      daemonLogFile.path,
       ...config.extraArgs,
     ];
     try {
-      await Process.start(
+      final process = await Process.start(
         binary,
         args,
-        workingDirectory: Directory.current.path,
-        mode: ProcessStartMode.detached,
+        workingDirectory: workingDirectory,
+        mode: ProcessStartMode.detachedWithStdio,
       );
+      _logger.i(
+        'Starting local node: "$binary" ${args.join(' ')} '
+        '(cwd=$workingDirectory, log=${daemonLogFile.path})',
+      );
+      unawaited(_pipeLauncherLogs(process, launcherLogFile));
+      final earlyExitCode = await _waitForEarlyExit(process);
+      if (earlyExitCode != null) {
+        _logger.w(
+          'Local node exited immediately with code $earlyExitCode. '
+          'See ${launcherLogFile.path} and ${daemonLogFile.path}',
+        );
+        return false;
+      }
     } catch (error) {
       _logger.w('Failed to start local node: $error');
       return false;
@@ -110,6 +130,39 @@ class WindowsLocalNodeService implements LocalNodeService {
     return _waitForRpc(config);
   }
 
+  Future<void> _pipeLauncherLogs(Process process, File logFile) async {
+    final sink = logFile.openWrite(mode: FileMode.writeOnlyAppend);
+    sink.writeln('=== ${DateTime.now().toIso8601String()} local node launch ===');
+    unawaited(
+      process.stdout
+          .transform(utf8.decoder)
+          .transform(const LineSplitter())
+          .forEach((line) => sink.writeln('[stdout] $line')),
+    );
+    unawaited(
+      process.stderr
+          .transform(utf8.decoder)
+          .transform(const LineSplitter())
+          .forEach((line) => sink.writeln('[stderr] $line')),
+    );
+    unawaited(
+      process.exitCode.then((code) async {
+        sink.writeln('[exit] $code');
+        await sink.flush();
+        await sink.close();
+      }),
+    );
+  }
+
+  Future<int?> _waitForEarlyExit(Process process) async {
+    const startupGrace = Duration(seconds: 2);
+    final result = await Future.any<Object?>([
+      process.exitCode,
+      Future<Object?>.delayed(startupGrace, () => null),
+    ]);
+    return result is int ? result : null;
+  }
+
   Future<bool> _waitForRpc(LocalNodeConfig config) async {
     const attempts = 20;
     for (var i = 0; i < attempts; i++) {