Restructure solution layout by module

src/Scanner/StellaOps.Scanner.Worker/Processing/ScanJobProcessor.cs

@@ -0,0 +1,65 @@
+using System;
+using System.Collections.Generic;
+using System.Threading;
+using System.Threading.Tasks;
+using Microsoft.Extensions.Logging;
+
+namespace StellaOps.Scanner.Worker.Processing;
+
+public sealed class ScanJobProcessor
+{
+    private readonly IReadOnlyDictionary<string, IScanStageExecutor> _executors;
+    private readonly ScanProgressReporter _progressReporter;
+    private readonly ILogger<ScanJobProcessor> _logger;
+
+    public ScanJobProcessor(IEnumerable<IScanStageExecutor> executors, ScanProgressReporter progressReporter, ILogger<ScanJobProcessor> logger)
+    {
+        _progressReporter = progressReporter ?? throw new ArgumentNullException(nameof(progressReporter));
+        _logger = logger ?? throw new ArgumentNullException(nameof(logger));
+
+        var map = new Dictionary<string, IScanStageExecutor>(StringComparer.OrdinalIgnoreCase);
+        foreach (var executor in executors ?? Array.Empty<IScanStageExecutor>())
+        {
+            if (executor is null || string.IsNullOrWhiteSpace(executor.StageName))
+            {
+                continue;
+            }
+
+            map[executor.StageName] = executor;
+        }
+
+        foreach (var stage in ScanStageNames.Ordered)
+        {
+            if (map.ContainsKey(stage))
+            {
+                continue;
+            }
+
+            map[stage] = new NoOpStageExecutor(stage);
+            _logger.LogDebug("No executor registered for stage {Stage}; using no-op placeholder.", stage);
+        }
+
+        _executors = map;
+    }
+
+    public async ValueTask ExecuteAsync(ScanJobContext context, CancellationToken cancellationToken)
+    {
+        ArgumentNullException.ThrowIfNull(context);
+
+        foreach (var stage in ScanStageNames.Ordered)
+        {
+            cancellationToken.ThrowIfCancellationRequested();
+
+            if (!_executors.TryGetValue(stage, out var executor))
+            {
+                continue;
+            }
+
+            await _progressReporter.ExecuteStageAsync(
+                context,
+                stage,
+                executor.ExecuteAsync,
+                cancellationToken).ConfigureAwait(false);
+        }
+    }
+}