Add one model host per provider and the unwrapping walk

app/MindWork AI Studio/Models/Hosting/Hosts/HostHetzner.cs

@@ -0,0 +1,15 @@
+using AIStudio.Provider;
+
+namespace AIStudio.Models.Hosting.Hosts;
+
+/// <summary>
+/// Hetzner's inference offering, which serves open weights under their plain names.
+/// </summary>
+public sealed class HostHetzner : ModelHost
+{
+    /// <inheritdoc />
+    public override LLMProviders Provider => LLMProviders.HETZNER;
+
+    /// <inheritdoc />
+    public override ModelSource Source => new("https://experiments.hetzner.com/docs/inference", new DateOnly(2026, 9, 11), "Open weights named plainly, served through the OpenAI-compatible chat completion API.");
+}