feat(lmxproxy): phase 3 — host gRPC server, security, configuration, service hosting

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

lmxproxy/src/ZB.MOM.WW.LmxProxy.Host/Program.cs

@@ -1,10 +1,78 @@
+using System;
+using Microsoft.Extensions.Configuration;
+using Serilog;
+using Topshelf;
+using ZB.MOM.WW.LmxProxy.Host.Configuration;
+
 namespace ZB.MOM.WW.LmxProxy.Host
 {
     internal static class Program
     {
-        static void Main(string[] args)
+        static int Main(string[] args)
         {
-            // Placeholder - Phase 3 will implement full Topshelf startup.
+            // 1. Build configuration
+            var configuration = new ConfigurationBuilder()
+                .SetBasePath(AppDomain.CurrentDomain.BaseDirectory)
+                .AddJsonFile("appsettings.json", optional: false, reloadOnChange: false)
+                .AddEnvironmentVariables()
+                .Build();
+
+            // 2. Configure Serilog
+            Log.Logger = new LoggerConfiguration()
+                .ReadFrom.Configuration(configuration)
+                .Enrich.FromLogContext()
+                .Enrich.WithMachineName()
+                .Enrich.WithThreadId()
+                .CreateLogger();
+
+            try
+            {
+                // 3. Bind configuration
+                var config = new LmxProxyConfiguration();
+                configuration.Bind(config);
+
+                // 4. Configure Topshelf
+                var exitCode = HostFactory.Run(host =>
+                {
+                    host.UseSerilog();
+
+                    host.Service<LmxProxyService>(service =>
+                    {
+                        service.ConstructUsing(() => new LmxProxyService(config));
+                        service.WhenStarted(s => s.Start());
+                        service.WhenStopped(s => s.Stop());
+                        service.WhenPaused(s => s.Pause());
+                        service.WhenContinued(s => s.Continue());
+                        service.WhenShutdown(s => s.Stop());
+                    });
+
+                    host.SetServiceName("ZB.MOM.WW.LmxProxy.Host");
+                    host.SetDisplayName("SCADA Bridge LMX Proxy");
+                    host.SetDescription("gRPC proxy for AVEVA System Platform via MXAccess COM API");
+
+                    host.StartAutomatically();
+                    host.EnablePauseAndContinue();
+
+                    host.EnableServiceRecovery(recovery =>
+                    {
+                        recovery.RestartService(config.ServiceRecovery.FirstFailureDelayMinutes);
+                        recovery.RestartService(config.ServiceRecovery.SecondFailureDelayMinutes);
+                        recovery.RestartService(config.ServiceRecovery.SubsequentFailureDelayMinutes);
+                        recovery.SetResetPeriod(config.ServiceRecovery.ResetPeriodDays);
+                    });
+                });
+
+                return (int)exitCode;
+            }
+            catch (Exception ex)
+            {
+                Log.Fatal(ex, "LmxProxy service terminated unexpectedly");
+                return 1;
+            }
+            finally
+            {
+                Log.CloseAndFlush();
+            }
         }
     }
 }