Prefer Thread border router instance name (#22378)

Instead of using the model name (which is the same for all border
routers of the same make and model), use the instance name as the
border router name.

Builds on home-assistant/core#127253.

src/data/thread.ts

@@ -1,6 +1,7 @@
 import { HomeAssistant } from "../types";
 
 export interface ThreadRouter {
+  instance_name: string;
   addresses: [string];
   border_agent_id: string | null;
   brand: "google" | "apple" | "homeassistant";

src/panels/config/integrations/integration-panels/thread/thread-config-panel.ts

@@ -234,7 +234,8 @@ export class ThreadConfigPanel extends SubscribeMixin(LitElement) {
                   @error=${this._onImageError}
                   @load=${this._onImageLoad}
                 />
-                ${router.model_name ||
+                ${router.instance_name ||
+                router.model_name ||
                 router.server?.replace(".local.", "") ||
                 ""}
                 <span slot="secondary">${router.server}</span>