Provide output logs when the process launch fails.

Author: gspencergoog

pkgs/dart_mcp_server/lib/src/mixins/flutter_launcher.dart

@@ -170,13 +170,15 @@ base mixin FlutterLauncherSupport
             LoggingLevel.info,
             'Flutter application ${process!.pid} exited with code $exitCode.',
           );
-          _runningApps.remove(process.pid);
           if (!completer.isCompleted) {
+            final logOutput = _runningApps[process.pid]?.logs.join('\n');
             completer.completeError(
               'Flutter application exited with code $exitCode before the DTD '
-              'URI was found.',
+              'URI was found, with log output:\n$logOutput',
             );
           }
+          _runningApps.remove(process.pid);
+
           // Cancel subscriptions after all processing is done.
           await stdoutSubscription.cancel();
           await stderrSubscription.cancel();

pkgs/dart_mcp_server/pubspec.yaml

@@ -40,7 +40,7 @@ dependencies:
   yaml: ^3.1.3
 
 dev_dependencies:
-  analyzer: ^7.5.2
+  analyzer: ^8.2.0
   dart_flutter_team_lints: ^3.2.1
   pub_semver: ^2.2.0
   test: ^1.25.15