Added the visual briefing assistant (#893)

app/MindWork AI Studio/Assistants/VisualBriefing/VisualBriefingBuildStatus.cs

@@ -0,0 +1,40 @@
+using System.Text.Json.Serialization;
+
+namespace AIStudio.Assistants.VisualBriefing;
+
+/// <summary>
+/// Describes the lifecycle state of a persistent visual briefing build.
+/// </summary>
+[JsonConverter(typeof(JsonStringEnumConverter<VisualBriefingBuildStatus>))]
+public enum VisualBriefingBuildStatus
+{
+    /// <summary>
+    /// The build is active or can be resumed.
+    /// </summary>
+    ACTIVE,
+
+    /// <summary>
+    /// The build committed an immutable revision.
+    /// </summary>
+    COMPLETED,
+
+    /// <summary>
+    /// The build failed with a safe, persisted failure description.
+    /// </summary>
+    FAILED,
+
+    /// <summary>
+    /// The build was canceled.
+    /// </summary>
+    CANCELED,
+
+    /// <summary>
+    /// The build inputs changed and the build was archived.
+    /// </summary>
+    SUPERSEDED,
+
+    /// <summary>
+    /// A valid content update is structurally incompatible and can continue as a rebuild.
+    /// </summary>
+    AWAITING_REBUILD,
+}