[browser] Emit hosting messages expected by debug proxy launcher (#118775)

Author: maraf

src/mono/browser/debugger/BrowserDebugHost/DebugProxyHost.cs

@@ -53,7 +53,6 @@ public static async Task RunDevToolsProxyAsync(ProxyOptions options, string[] ar
             .ConfigureServices(services =>
             {
                 services.AddSingleton(loggerFactory);
-                services.AddLogging(configure => configure.AddSimpleConsole().AddFilter(null, LogLevel.Information));
                 services.AddSingleton(Options.Create(options));
                 services.AddRouting();
             })

src/mono/browser/debugger/BrowserDebugHost/Program.cs

@@ -7,6 +7,8 @@
 using Microsoft.Extensions.Configuration;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Logging;
+using Microsoft.Extensions.Logging.Abstractions;
+using Microsoft.Extensions.Logging.Console;
 
 #nullable enable
 
@@ -23,16 +25,24 @@ public static async Task Main(string[] args)
 
             using ILoggerFactory loggerFactory = LoggerFactory.Create(builder =>
             {
-                builder.AddSimpleConsole(options =>
-                        {
-                            options.TimestampFormat = "[HH:mm:ss] ";
-                        })
-                        .AddFilter("DevToolsProxy", LogLevel.Information)
-                        .AddFilter("FirefoxMonoProxy", LogLevel.Information)
-                        .AddFilter(null, LogLevel.Warning);
+                builder
+                    .AddConsole(options => options.FormatterName = "messageOnly") // Emit messages as expected by DebugProxyLauncher.cs
+                    .AddConsoleFormatter<MessageOnlyFormatter, ConsoleFormatterOptions>()
+                    .AddFilter("Microsoft.Hosting.Lifetime", LogLevel.Information)
+                    .AddFilter("DevToolsProxy", LogLevel.Information)
+                    .AddFilter("FirefoxMonoProxy", LogLevel.Information)
+                    .AddFilter(null, LogLevel.Warning);
             });
 
             await DebugProxyHost.RunDebugProxyAsync(options, args, loggerFactory, CancellationToken.None);
         }
     }
+
+    public class MessageOnlyFormatter : ConsoleFormatter
+    {
+        public MessageOnlyFormatter() : base("messageOnly") { }
+
+        public override void Write<TState>(in LogEntry<TState> logEntry, IExternalScopeProvider? scopeProvider, TextWriter textWriter)
+            => textWriter.WriteLine(logEntry.Formatter(logEntry.State, logEntry.Exception));
+    }
 }