Port the OpenAI families and add the model registry

app/MindWork AI Studio/Models/OpenAI/OpenAIEmbeddingFamily.cs

@@ -0,0 +1,35 @@
+using AIStudio.Provider;
+
+using static AIStudio.Provider.Capability;
+
+namespace AIStudio.Models.OpenAI;
+
+/// <summary>
+/// OpenAI's embedding models, which turn text into a vector and answer nothing.
+/// </summary>
+/// <remarks>
+/// The previous rules had no idea these existed. They fell through to the OpenAI fallback and were
+/// told they see images, call functions, and search the web -- an answer with nothing right about
+/// it, for models the app asks for through a separate method of its own.
+///
+/// The generation is named rather than the prefix "text-embedding": Google and Alibaba Cloud name
+/// their own embedding models the same way, and those are their models, not these.
+/// </remarks>
+public sealed class OpenAIEmbeddingFamily : ModelFamily
+{
+    /// <inheritdoc />
+    public override ModelVendor Vendor => ModelVendor.OPEN_AI;
+
+    /// <inheritdoc />
+    public override ModelSource Source => new("https://platform.openai.com/docs/guides/embeddings", new DateOnly(2026, 9, 11), "The app lists these under IProvider.GetEmbeddingModels, which is where the statement that they embed comes from.");
+
+    /// <inheritdoc />
+    protected override void Declare(ModelFamilyBuilder builder)
+    {
+        builder.Rule("text-embedding-3").AsPrefix()
+            .Capabilities(TEXT_INPUT | EMBEDDING)
+            .Kind(ModelKind.EMBEDDING);
+
+        builder.Rule("text-embedding-ada").AsPrefix().Inherits();
+    }
+}