Add the model matching engine and make capabilities a flags enum

app/MindWork AI Studio/Models/ModelProfileChange.cs

@@ -0,0 +1,79 @@
+using AIStudio.Provider;
+
+namespace AIStudio.Models;
+
+/// <summary>
+/// What a rule states about a model, as a change to what is known so far.
+/// </summary>
+/// <remarks>
+/// A selector applies its change to nothing and so states a whole profile; a modifier applies its
+/// change to whatever the selector decided. One type for both, because "adds web search" and "takes
+/// web search away again" are the same kind of sentence.
+///
+/// Everything left unsaid stays as it was. That is what lets a rule for a variant say only what
+/// makes the variant different, instead of repeating the family it belongs to.
+/// </remarks>
+public sealed record ModelProfileChange
+{
+    /// <summary>
+    /// A change which states nothing.
+    /// </summary>
+    public static readonly ModelProfileChange NOTHING = new();
+
+    /// <summary>
+    /// Capabilities the model has.
+    /// </summary>
+    public Capability Adds { get; init; }
+
+    /// <summary>
+    /// Capabilities the model does not have, applied after the ones it has.
+    /// </summary>
+    public Capability Removes { get; init; }
+
+    /// <summary>
+    /// How the model reasons, or null to leave that as it was.
+    /// </summary>
+    public ReasoningSupport? Reasoning { get; init; }
+
+    /// <summary>
+    /// What the model is made for, or null to leave that as it was.
+    /// </summary>
+    public ModelKind? Kind { get; init; }
+
+    /// <summary>
+    /// The context window, or null to leave it as it was.
+    /// </summary>
+    public ContextWindow? Context { get; init; }
+
+    /// <summary>
+    /// The tokenizer reference, or null to leave it as it was.
+    /// </summary>
+    public TokenizerRef? Tokenizer { get; init; }
+
+    /// <summary>
+    /// The image limits, or null to leave them as they were.
+    /// </summary>
+    public ImageLimits? Images { get; init; }
+
+    /// <summary>
+    /// Applies this change to a profile.
+    /// </summary>
+    /// <remarks>
+    /// The three reasoning members of the capability enum are dropped here rather than trusted to
+    /// stay out: they are the vocabulary a person writes an override in, and a profile which
+    /// carried them could say that a model both always reasons and reasons on request. A rule which
+    /// declares one has still made a mistake, which is why the tests and the verification run look
+    /// for it instead of relying on this line to hide it.
+    /// </remarks>
+    /// <param name="profile">What is known so far.</param>
+    /// <returns>What is known afterwards.</returns>
+    public ModelProfile ApplyTo(in ModelProfile profile) => profile with
+    {
+        Capabilities = (profile.Capabilities | this.Adds) & ~this.Removes & ~ModelProfile.REASONING_VOCABULARY,
+        Reasoning = this.Reasoning ?? profile.Reasoning,
+        Kind = this.Kind ?? profile.Kind,
+        Context = this.Context ?? profile.Context,
+        Tokenizer = this.Tokenizer ?? profile.Tokenizer,
+        Images = this.Images ?? profile.Images,
+    };
+}