UI: add Broadcast — run a command on the given session across all online clients

Daemon: drop RELAY_SECRET; auth via HF token only

Drop app-level RELAY_SECRET; private Space + HF token is the auth

Harden: per-session workers, SIGINT-children (keep session), stdin /dev/null, exact marker, put size cap, shell reaper, telemetry off

Harden: fail-closed+const-time auth, id validation, FILES_DIR reaper+trim, server size cap, copy-outside-lock, api_poll .get(), no analytics

Pin gradio 6.10.0 (fixes api-info bool bug from gr.File on 5.9.1); theme->launch

daemon: handle put/get file transfers

Add file transfer (push/pull, <=100MB); dropdown allow_custom_value

daemon: default client id = user@ip

UI: skip no-op repaints to stop dropdown/output flicker

daemon: support gradio_client token kwarg rename

Add poller daemon (client.py)

Initial NII Relay

initial commit