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

app/MindWork AI Studio/Tools/Services/Indexing/RunShare.cs

@@ -0,0 +1,20 @@
+namespace AIStudio.Tools.Services.Indexing;
+
+/// <summary>
+/// How much work one indexing run does at most, before it leaves the rest to another run.
+/// </summary>
+/// <remarks>
+/// Only the work on documents counts, cf. DocumentRunProgress.HasDoneItsShare: the clock starts right
+/// before the first one. Whatever a kind of data source does before, e.g. listing the files of a
+/// folder, every run has to do anew, and counting it would leave a large folder little time for its
+/// documents.
+/// </remarks>
+/// <param name="MaxDuration">How long a run works on documents at most. More than zero.</param>
+/// <param name="MaxDocuments">How many documents a run reads at most, whether that works or not. Null when only the time counts.</param>
+internal sealed record RunShare(TimeSpan MaxDuration, int? MaxDocuments = null)
+{
+    /// <summary>
+    /// How long a run works on documents, unless its kind of data source has a reason for another time.
+    /// </summary>
+    public static readonly TimeSpan DEFAULT_DURATION = TimeSpan.FromMinutes(5);
+}