feat(host): add Serilog logging with console and file sinks

Configure structured logging following logging_style.md guidelines with
daily rolling log files (30-day retention) and proper shutdown handling.

NEW/src/JdeScoping.Host/JdeScoping.Host.csproj

@@ -14,6 +14,10 @@
   <ItemGroup>
     <PackageReference Include="Microsoft.AspNetCore.Components.WebAssembly.Server" Version="10.0.1" />
     <PackageReference Include="Microsoft.Extensions.Hosting.WindowsServices" Version="10.0.1" />
+    <PackageReference Include="Serilog" Version="4.*" />
+    <PackageReference Include="Serilog.Extensions.Logging" Version="8.*" />
+    <PackageReference Include="Serilog.Sinks.Console" Version="6.*" />
+    <PackageReference Include="Serilog.Sinks.File" Version="6.*" />
   </ItemGroup>
 
   <PropertyGroup>

NEW/src/JdeScoping.Host/Program.cs

@@ -4,82 +4,117 @@ using JdeScoping.DataSync.Options;
 using JdeScoping.ExcelIO.Options;
 using JdeScoping.Database;
 using JdeScoping.Host.Startup;
-using Microsoft.Extensions.Logging;
 using Microsoft.Extensions.Options;
+using Serilog;
+using Serilog.Events;
 
-var builder = WebApplication.CreateBuilder(args);
+// Configure Serilog with console and daily rolling file
+var logsPath = Path.Combine(AppContext.BaseDirectory, "logs");
+Directory.CreateDirectory(logsPath);
 
-// Windows Service support (no-op on non-Windows)
+Log.Logger = new LoggerConfiguration()
-builder.Host.UseWindowsService();
+    .MinimumLevel.Information()
+    .MinimumLevel.Override("Microsoft", LogEventLevel.Warning)
+    .MinimumLevel.Override("Microsoft.AspNetCore", LogEventLevel.Warning)
+    .Enrich.FromLogContext()
+    .WriteTo.Console(
+        outputTemplate: "{Timestamp:HH:mm:ss} [{Level:u3}] {Message:lj}{NewLine}{Exception}")
+    .WriteTo.File(
+        path: Path.Combine(logsPath, "scoping-.log"),
+        rollingInterval: RollingInterval.Day,
+        retainedFileCountLimit: 30,
+        outputTemplate: "{Timestamp:yyyy-MM-dd HH:mm:ss.fff zzz} [{Level:u3}] {Message:lj}{NewLine}{Exception}")
+    .CreateLogger();
 
-// Run database migrations (skip in Testing environment)
+try
-// Note: IDatabaseMigrator interface enables mocking for integration tests
-if (!builder.Environment.IsEnvironment("Testing"))
 {
-    // Create early logger for startup diagnostics
+    var builder = WebApplication.CreateBuilder(args);
-    using var loggerFactory = LoggerFactory.Create(b => b
-        .AddConfiguration(builder.Configuration.GetSection("Logging"))
-        .AddConsole());
-    var startupLogger = loggerFactory.CreateLogger("JdeScoping.Host.Startup");
 
-    IDatabaseMigrator migrator = new DatabaseMigrator(builder.Configuration);
+    // Windows Service support (no-op on non-Windows)
-    var migrationResult = migrator.Migrate();
+    builder.Host.UseWindowsService();
 
-    if (!migrationResult.Successful)
+    // Replace default logging with Serilog
+    builder.Services.AddLogging(logging =>
     {
-        startupLogger.LogError(migrationResult.Error, "Database migration failed: {ErrorMessage}", migrationResult.Error?.Message);
+        logging.ClearProviders();
-        return 1;
+        logging.AddSerilog(dispose: true);
-    }
+    });
-}
 
-// ASP.NET Core services
+    // Run database migrations (skip in Testing environment)
-builder.Services.AddRazorPages();
+    // Note: IDatabaseMigrator interface enables mocking for integration tests
-
+    if (!builder.Environment.IsEnvironment("Testing"))
-// Module registration (in dependency order)
-builder.Services
-    .AddDataAccess(builder.Configuration)       // 1. Database access + search processing
-    .AddInfrastructure(builder.Configuration)   // 2. Infrastructure (JDE/CMS/Auth)
-    .AddDataSyncServices(builder.Configuration) // 3. Data sync background service
-    .AddExcelIO(builder.Configuration)      // 4. Result export
-    .AddWebApi(builder.Configuration);          // 5. Web API (controllers, auth, SignalR)
-
-var app = builder.Build();
-
-// Configuration validation (skip in Testing environment)
-if (!app.Environment.IsEnvironment("Testing"))
-{
-    var configLogger = app.Services.GetRequiredService<ILoggerFactory>()
-        .CreateLogger("JdeScoping.Host.ConfigurationValidation");
-
-    if (!ConfigurationValidationRunner.ValidateConfiguration(app.Services, configLogger))
     {
-        configLogger.LogCritical("Application startup aborted due to configuration validation failures");
+        IDatabaseMigrator migrator = new DatabaseMigrator(builder.Configuration);
-        return 1;
+        var migrationResult = migrator.Migrate();
+
+        if (!migrationResult.Successful)
+        {
+            Log.Error(migrationResult.Error, "Database migration failed: {ErrorMessage}", migrationResult.Error?.Message);
+            return 1;
+        }
     }
+
+    // ASP.NET Core services
+    builder.Services.AddRazorPages();
+
+    // Module registration (in dependency order)
+    builder.Services
+        .AddDataAccess(builder.Configuration)       // 1. Database access + search processing
+        .AddInfrastructure(builder.Configuration)   // 2. Infrastructure (JDE/CMS/Auth)
+        .AddDataSyncServices(builder.Configuration) // 3. Data sync background service
+        .AddExcelIO(builder.Configuration)      // 4. Result export
+        .AddWebApi(builder.Configuration);          // 5. Web API (controllers, auth, SignalR)
+
+    var app = builder.Build();
+
+    // Configuration validation (skip in Testing environment)
+    if (!app.Environment.IsEnvironment("Testing"))
+    {
+        var configLogger = app.Services.GetRequiredService<ILoggerFactory>()
+            .CreateLogger("JdeScoping.Host.ConfigurationValidation");
+
+        if (!ConfigurationValidationRunner.ValidateConfiguration(app.Services, configLogger))
+        {
+            Log.Fatal("Application startup aborted due to configuration validation failures");
+            return 1;
+        }
+    }
+
+    // Startup validation - verify critical services are registered
+    ValidateServices(app.Services);
+
+    // Configure the HTTP request pipeline
+    if (app.Environment.IsDevelopment())
+    {
+        app.UseWebAssemblyDebugging();
+    }
+
+    app.UseStaticFiles();
+    app.UseBlazorFrameworkFiles();
+    app.UseRouting();
+
+    // Configure Web API middleware (authentication, authorization, controllers, SignalR hub)
+    app.UseWebApi();
+
+    app.MapRazorPages();
+    app.MapFallbackToFile("index.html");
+
+    // Register shutdown handler for clean Serilog disposal
+    app.Lifetime.ApplicationStopping.Register(Log.CloseAndFlush);
+
+    app.Run();
+
+    return 0;
 }
-
+catch (Exception ex)
-// Startup validation - verify critical services are registered
-ValidateServices(app.Services);
-
-// Configure the HTTP request pipeline
-if (app.Environment.IsDevelopment())
 {
-    app.UseWebAssemblyDebugging();
+    Log.Fatal(ex, "Application terminated unexpectedly");
+    return 1;
+}
+finally
+{
+    Log.CloseAndFlush();
 }
-
-app.UseStaticFiles();
-app.UseBlazorFrameworkFiles();
-app.UseRouting();
-
-// Configure Web API middleware (authentication, authorization, controllers, SignalR hub)
-app.UseWebApi();
-
-app.MapRazorPages();
-app.MapFallbackToFile("index.html");
-
-app.Run();
-
-return 0;
 
 // Validates that critical services are properly registered
 static void ValidateServices(IServiceProvider services)