Added the Model Comparison assistant for blind comparisons of two models (#1009)

Co-authored-by: Thorsten Sommer <SommerEngineering@users.noreply.github.com>

app/MindWork AI Studio/Assistants/ModelComparison/ModelComparisonTally.cs

@@ -0,0 +1,64 @@
+namespace AIStudio.Assistants.ModelComparison;
+
+/// <summary>
+/// How often each model came out ahead across several runs: by the votes of the user, or by the verdicts of the judge.
+/// </summary>
+/// <remarks>
+/// Counted in models, never in columns: the column a model stood in was drawn fresh for every run, so only the model
+/// stays comparable across runs. A run without a usable choice, such as one the user did not vote on, or one whose
+/// judge gave no usable verdict, counts toward TotalRunCount, but toward nothing else.
+/// </remarks>
+public sealed record ModelComparisonTally
+{
+    /// <summary>
+    /// How many runs there were, counted or not.
+    /// </summary>
+    public required int TotalRunCount { get; init; }
+
+    public required int FirstModelWins { get; init; }
+
+    public required int SecondModelWins { get; init; }
+
+    public required int Ties { get; init; }
+
+    /// <summary>
+    /// How many runs had a usable choice and were counted.
+    /// </summary>
+    public int ScoredRunCount => this.FirstModelWins + this.SecondModelWins + this.Ties;
+
+    /// <summary>
+    /// How many runs had no usable choice and were left out.
+    /// </summary>
+    public int UnscoredRunCount => this.TotalRunCount - this.ScoredRunCount;
+
+    /// <summary>
+    /// The tally of no runs at all.
+    /// </summary>
+    public static readonly ModelComparisonTally NONE = new()
+    {
+        TotalRunCount = 0,
+        FirstModelWins = 0,
+        SecondModelWins = 0,
+        Ties = 0,
+    };
+
+    /// <summary>
+    /// Counts the choices of several runs.
+    /// </summary>
+    /// <param name="choices">The choice of each run, already turned from a column into a model; null for a run without a usable choice.</param>
+    /// <returns>The tally.</returns>
+    public static ModelComparisonTally Of(IEnumerable<ModelComparisonModelChoice?> choices) => choices.Aggregate(NONE, (tally, choice) => tally.Plus(choice));
+
+    /// <summary>
+    /// Counts one more run.
+    /// </summary>
+    /// <param name="choice">The choice of the run, already turned from a column into a model; null for a run without a usable choice.</param>
+    /// <returns>The tally with the run.</returns>
+    public ModelComparisonTally Plus(ModelComparisonModelChoice? choice) => this with
+    {
+        TotalRunCount = this.TotalRunCount + 1,
+        FirstModelWins = this.FirstModelWins + (choice is ModelComparisonModelChoice.FIRST ? 1 : 0),
+        SecondModelWins = this.SecondModelWins + (choice is ModelComparisonModelChoice.SECOND ? 1 : 0),
+        Ties = this.Ties + (choice is ModelComparisonModelChoice.TIE ? 1 : 0),
+    };
+}