Refactor code structure for improved readability and maintainability

src/Scanner/StellaOps.Scanner.WebService/Endpoints/ScanEndpoints.cs

@@ -71,6 +71,12 @@ internal static class ScanEndpoints
             .Produces<RubyPackagesResponse>(StatusCodes.Status200OK)
             .Produces(StatusCodes.Status404NotFound)
             .RequireAuthorization(ScannerPolicies.ScansRead);
+
+        scans.MapGet("/{scanId}/bun-packages", HandleBunPackagesAsync)
+            .WithName("scanner.scans.bun-packages")
+            .Produces<BunPackagesResponse>(StatusCodes.Status200OK)
+            .Produces(StatusCodes.Status404NotFound)
+            .RequireAuthorization(ScannerPolicies.ScansRead);
     }
 
     private static async Task<IResult> HandleSubmitAsync(
@@ -497,6 +503,63 @@ internal static class ScanEndpoints
         return Json(response, StatusCodes.Status200OK);
     }
 
+    private static async Task<IResult> HandleBunPackagesAsync(
+        string scanId,
+        IScanCoordinator coordinator,
+        IBunPackageInventoryStore inventoryStore,
+        HttpContext context,
+        CancellationToken cancellationToken)
+    {
+        ArgumentNullException.ThrowIfNull(coordinator);
+        ArgumentNullException.ThrowIfNull(inventoryStore);
+
+        if (!ScanId.TryParse(scanId, out var parsed))
+        {
+            return ProblemResultFactory.Create(
+                context,
+                ProblemTypes.Validation,
+                "Invalid scan identifier",
+                StatusCodes.Status400BadRequest,
+                detail: "Scan identifier is required.");
+        }
+
+        var inventory = await inventoryStore.GetAsync(parsed.Value, cancellationToken).ConfigureAwait(false);
+        if (inventory is null)
+        {
+            BunPackageInventory? fallback = null;
+            if (!LooksLikeScanId(scanId))
+            {
+                var snapshot = await TryResolveSnapshotAsync(scanId, coordinator, cancellationToken).ConfigureAwait(false);
+                if (snapshot is not null)
+                {
+                    fallback = await inventoryStore.GetAsync(snapshot.ScanId.Value, cancellationToken).ConfigureAwait(false);
+                }
+            }
+
+            if (fallback is null)
+            {
+                return ProblemResultFactory.Create(
+                    context,
+                    ProblemTypes.NotFound,
+                    "Bun packages not found",
+                    StatusCodes.Status404NotFound,
+                    detail: "Bun package inventory is not available for the requested scan.");
+            }
+
+            inventory = fallback;
+        }
+
+        var response = new BunPackagesResponse
+        {
+            ScanId = inventory.ScanId,
+            ImageDigest = inventory.ImageDigest,
+            GeneratedAt = inventory.GeneratedAtUtc,
+            Packages = inventory.Packages
+        };
+
+        return Json(response, StatusCodes.Status200OK);
+    }
+
     private static IReadOnlyDictionary<string, string> NormalizeMetadata(IDictionary<string, string> metadata)
     {
         if (metadata is null || metadata.Count == 0)