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/ModelComparisonModelIdentity.cs

@@ -0,0 +1,61 @@
+using System.Text.Json.Serialization;
+
+using AIStudio.Provider;
+
+namespace AIStudio.Assistants.ModelComparison;
+
+/// <summary>
+/// Which model took part in a stored comparison.
+/// </summary>
+/// <remarks>
+/// The statistics count a model across comparisons by its provider, its host, and its ID, not by the provider entry
+/// of the settings: the user may delete or rename that entry, and two entries may point to the same model. Only a
+/// self-hosted model has a host of its own; two servers may run models of the same name which are not the same.
+/// </remarks>
+public sealed record ModelComparisonModelIdentity
+{
+    /// <summary>
+    /// The kind of provider which ran the model.
+    /// </summary>
+    public LLMProviders LLMProvider { get; set; } = LLMProviders.NONE;
+
+    /// <summary>
+    /// The address of the server of a self-hosted model; empty for every other provider.
+    /// </summary>
+    public string Hostname { get; set; } = string.Empty;
+
+    /// <summary>
+    /// The ID of the model at its provider.
+    /// </summary>
+    public string ModelId { get; set; } = string.Empty;
+
+    /// <summary>
+    /// The name the comparison showed for the model, for the statistics to show it again.
+    /// </summary>
+    public string Label { get; set; } = string.Empty;
+
+    /// <summary>
+    /// Gets the identity of the model of a provider entry.
+    /// </summary>
+    /// <param name="provider">The provider entry, with its model.</param>
+    /// <returns>The identity.</returns>
+    public static ModelComparisonModelIdentity Of(AIStudio.Settings.Provider provider) => new()
+    {
+        LLMProvider = provider.UsedLLMProvider,
+        Hostname = provider.IsSelfHosted ? provider.Hostname : string.Empty,
+        ModelId = provider.Model.Id,
+        Label = provider.ToString(),
+    };
+
+    /// <summary>
+    /// Gets what tells this model apart from others, whatever the label.
+    /// </summary>
+    [JsonIgnore]
+    public ModelComparisonModelKey Key => ModelComparisonModelKey.Of(this.LLMProvider, this.Hostname, this.ModelId);
+
+    /// <summary>
+    /// Whether both identities name the same model, whatever the label.
+    /// </summary>
+    /// <param name="other">The other identity.</param>
+    public bool IsSameModelAs(ModelComparisonModelIdentity other) => this.Key == other.Key;
+}