Add Vexer connector suite, format normalizers, and tooling

src/StellaOps.Vexer.Connectors.Cisco.CSAF/Configuration/CiscoConnectorOptions.cs

@@ -0,0 +1,58 @@
+using System.ComponentModel.DataAnnotations;
+
+namespace StellaOps.Vexer.Connectors.Cisco.CSAF.Configuration;
+
+public sealed class CiscoConnectorOptions : IValidatableObject
+{
+    public const string HttpClientName = "cisco-csaf";
+
+    /// <summary>
+    /// Endpoint for Cisco CSAF provider metadata discovery.
+    /// </summary>
+    [Required]
+    public string MetadataUri { get; set; } = "https://api.security.cisco.com/.well-known/csaf/provider-metadata.json";
+
+    /// <summary>
+    /// Optional bearer token used when Cisco endpoints require authentication.
+    /// </summary>
+    public string? ApiToken { get; set; }
+
+    /// <summary>
+    /// How long provider metadata remains cached.
+    /// </summary>
+    public TimeSpan MetadataCacheDuration { get; set; } = TimeSpan.FromHours(6);
+
+    /// <summary>
+    /// Whether to prefer offline snapshots when fetching metadata.
+    /// </summary>
+    public bool PreferOfflineSnapshot { get; set; }
+
+    /// <summary>
+    /// When set, provider metadata will be persisted to the given file path.
+    /// </summary>
+    public bool PersistOfflineSnapshot { get; set; }
+
+    public string? OfflineSnapshotPath { get; set; }
+
+    public IEnumerable<ValidationResult> Validate(ValidationContext validationContext)
+    {
+        if (string.IsNullOrWhiteSpace(MetadataUri))
+        {
+            yield return new ValidationResult("MetadataUri must be provided.", new[] { nameof(MetadataUri) });
+        }
+        else if (!Uri.TryCreate(MetadataUri, UriKind.Absolute, out _))
+        {
+            yield return new ValidationResult("MetadataUri must be an absolute URI.", new[] { nameof(MetadataUri) });
+        }
+
+        if (MetadataCacheDuration <= TimeSpan.Zero)
+        {
+            yield return new ValidationResult("MetadataCacheDuration must be greater than zero.", new[] { nameof(MetadataCacheDuration) });
+        }
+
+        if (PersistOfflineSnapshot && string.IsNullOrWhiteSpace(OfflineSnapshotPath))
+        {
+            yield return new ValidationResult("OfflineSnapshotPath must be provided when PersistOfflineSnapshot is enabled.", new[] { nameof(OfflineSnapshotPath) });
+        }
+    }
+}