fix(api): keep file event streams alive

- Disable the Quart response timeout for authenticated file event streams.
- Send SSE keepalives more often to avoid idle proxy disconnects.
- Treat remote stream interruptions as reconnectable disconnects in watch output.
- Bump NanoShare to 1.26.0 and the standalone CLI to 0.4.1.

cli/nanoshare_client/watch.py

@@ -55,7 +55,7 @@ def _remote_events_thread(args, flag: _ChangeFlag, stop: threading.Event) -> thr
                 flag.notify()
       except Exception as exc:
         if not stop.is_set():
-          print(f'remote event stream unavailable; retrying in 30s: {exc}', file=sys.stderr)
+          print(f'remote event stream disconnected; retrying in 30s: {exc}', file=sys.stderr)
           stop.wait(30)
       finally:
         if client: