Indexed large data sources in steps so the others get their turn (#1052)

app/MindWork AI Studio/Tools/Services/DataSourceQueueRequestResult.cs

@@ -0,0 +1,27 @@
+namespace AIStudio.Tools.Services;
+
+/// <summary>
+/// What became of a request to queue an indexing run, cf. DataSourceRunQueue.TryReserve.
+/// </summary>
+internal enum DataSourceQueueRequestResult
+{
+    /// <summary>
+    /// The data source has its place in the queue reserved, and whoever asked enqueues it now.
+    /// </summary>
+    QUEUED,
+
+    /// <summary>
+    /// The data source waits in the queue already, and the request merged into that run.
+    /// </summary>
+    ALREADY_QUEUED,
+
+    /// <summary>
+    /// The data source runs, and either has its follow-up run already or was asked for none.
+    /// </summary>
+    RUNNING,
+
+    /// <summary>
+    /// The data source runs, and gets one follow-up run once the current one completes.
+    /// </summary>
+    RUNNING_MARKED_PENDING,
+}