fix: normalize abort signals for telegram fetch

src/telegram/fetch.ts

@@ -1,11 +1,13 @@
+import { wrapFetchWithAbortSignal } from "../infra/fetch.js";
+
 // Bun-only: force native fetch to avoid grammY's Node shim under Bun.
 export function resolveTelegramFetch(proxyFetch?: typeof fetch): typeof fetch | undefined {
-  if (proxyFetch) return proxyFetch;
+  if (proxyFetch) return wrapFetchWithAbortSignal(proxyFetch);
   const fetchImpl = globalThis.fetch;
   const isBun = "Bun" in globalThis || Boolean(process?.versions?.bun);
   if (!isBun) return undefined;
   if (!fetchImpl) {
     throw new Error("fetch is not available; set channels.telegram.proxy in config");
   }
-  return fetchImpl;
+  return wrapFetchWithAbortSignal(fetchImpl);
 }