fix: add missing Next.js route handler for Telegram test endpoint

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

apps/backoffice/app/api/telegram/test/route.ts

@@ -0,0 +1,12 @@
+import { NextResponse } from "next/server";
+import { apiFetch } from "@/lib/api";
+
+export async function GET() {
+  try {
+    const data = await apiFetch("/telegram/test");
+    return NextResponse.json(data);
+  } catch (error) {
+    const message = error instanceof Error ? error.message : "Failed to test Telegram connection";
+    return NextResponse.json({ error: message }, { status: 500 });
+  }
+}