Replaced the anonymous request shapes of the providers with records

app/MindWork AI Studio/Provider/OpenAI/ChatCompletionFunctionTool.cs

@@ -0,0 +1,11 @@
+namespace AIStudio.Provider.OpenAI;
+
+/// <summary>
+/// The function tool definition shape expected by Chat Completions compatible APIs, with the function nested.
+/// </summary>
+public sealed record ChatCompletionFunctionTool
+{
+    public string Type { get; init; } = "function";
+
+    public ChatCompletionFunctionDeclaration Function { get; init; } = new();
+}